Topical review-special collection of the publications from the COST MD-GAS Action participants can be found here:
Publications acknowledging COST MD-GAS Action CA18212:
Will be continously updated.
Action publications co-authored by at least two Action participants from two countries participating in the Action:
- Naemi Florin, Alicja Domaracka, Patrick Rousseau, Michael Gatchell, Henning Zettergren, “Bond breaking and making in mixed clusters of fullerene and coronene molecules following keV-ion impact” arXiv preprint arXiv:2401.17638, vol. , (2024).[Bibtex]
@article{ author = {Naemi Florin, Alicja Domaracka, Patrick Rousseau, Michael Gatchell, Henning Zettergren}, title = {Bond breaking and making in mixed clusters of fullerene and coronene molecules following keV-ion impact}, journal = {arXiv preprint arXiv:2401.17638}, volume = {}, number = {}, abstract = {}, year = {2024}, type= {Article}, }
- Dario Barreiro-Lage, Giuseppe Mattioli, Chiara Nicolafrancesco, Patrick Rousseau, Aleksandar R Milosavljevic and Sergio Diaz-Tendero, “Inner-shell photoelectron spectroscopy unveils the interplay between hydrogen bonds and stacking in clusters of biomolecules in the gas phase: hypoxanthine clusters as a case study” IOP Science home Accessibility Help Journals Books Publishing Support Login Journal of Physics B: Atomic, Molecular and Optical Physics, vol. , (2024).[Bibtex]
@article{ author = {Dario Barreiro-Lage, Giuseppe Mattioli, Chiara Nicolafrancesco, Patrick Rousseau, Aleksandar R Milosavljevic and Sergio Diaz-Tendero}, title = {Inner-shell photoelectron spectroscopy unveils the interplay between hydrogen bonds and stacking in clusters of biomolecules in the gas phase: hypoxanthine clusters as a case study}, journal = { IOP Science home Accessibility Help Journals Books Publishing Support Login Journal of Physics B: Atomic, Molecular and Optical Physics}, volume = {}, number = {}, abstract = {}, year = {2024}, type= {Article}, }
- Péter Szabó, György Lendvay , “Theoretical dynamics studies of the CH3 + HBr -> CH4 + Br reaction: effects of isotope substitution and vibrational excitation of CH3” Phys. Chem. Chem. Phys., vol. 26, 14 (2024).[Bibtex]
@article{ author = {Péter Szabó, György Lendvay }, title = {Theoretical dynamics studies of the CH3 + HBr -> CH4 + Br reaction: effects of isotope substitution and vibrational excitation of CH3}, journal = {Phys. Chem. Chem. Phys.}, volume = {26}, number = {14}, abstract = {The rate coefficient for two deuterium substituted isotopologues of reaction CH3 + HBr → CH4 + Br has been determined using the quasiclassical trajectory (QCT) method. We used the analytical potential energy surface (PES) fitted to high-level ab initio points in earlier work. The PES exhibits a pre-reaction van der Waals complex and a submerged potential barrier. The rate coefficients of the deuterated isotopologue reactions, similarly to the pure-protium isotopologue, show significant deviation from the Arrhenius law, namely, the activation energy is negative below about 600 K and positive above it: k[CH3 + DBr] = 1.35 × 10−11 exp(− 2472/T) + 5.85 × 10−13 exp(335/T) and k[CD3 + HBr] = 2.73 × 10−11 exp(− 2739/T) + 1.46 × 10−12 exp(363/T). The CH3 + DBr reaction is slower by a factor of 1.8, whereas CD3 + HBr isotopologue is faster by a factor of 1.4 compared to the HBr + CH3 system across a wide temperature range. The isotope effects are interpreted in terms of the properties of various regions of the PES. Quantum state-resolved simulations revealed that the reaction of CH3 with HBr becomes slower when any of the vibrational modes of the methyl radical is excited. This contradicts the assumption that vibrational excitation of methyl radicals enhances its reactivity, which is of historical importance: this assumption was used as an argument against the existence of negative activation energy in a decade-long controversy in the 1980s and 1990s.}, year = {2024}, type= {article}, }
- Jelena Vukalović, Bratislav P. Marinković, Jaime Rosado, Francisco Blanco, Gustavo GarcÃa, Jelena B. Maljković, “Investigating theoretical and experimental cross sections for elastic electron scattering from isoflurane” Phys. Chem. Chem. Phys., vol. 26, 2 (2024).[Bibtex]
@article{ author = {Jelena Vukalović, Bratislav P. Marinković, Jaime Rosado, Francisco Blanco, Gustavo GarcÃa, Jelena B. Maljković}, title = {Investigating theoretical and experimental cross sections for elastic electron scattering from isoflurane}, journal = {Phys. Chem. Chem. Phys.}, volume = {26}, number = {2}, abstract = {We present a comprehensive analysis of elastic electron scattering from isoflurane in the intermediate energy range of 50–300 eV. This research is motivated by the significant impact of this molecule on global warming effects. We conducted this investigation through experimental measurements using a crossed-beam apparatus and covering a wide angular range from 25 to 125 degrees. Relative differential cross sections (DCSs) were obtained and subsequently normalized on an absolute scale by using the relative flow technique{,} with argon as the reference gas. These DCS values were then extrapolated and integrated to determine the experimental integral cross sections (ICSs). Additionally{,} we employed the independent atom model and the screening corrected additivity rule with incorporated Interference effects (IAM-SCAR+I) to calculate the theoretical differential and integral cross-sections. Remarkably{,} the calculated cross sections align closely with the experimental measurements across the entire energy and angular range. Furthermore{,} this study involved a comparison of the DCSs for isoflurane with previously published DCS values for two other volatile anesthetics{,} sevoflurane and halothane.}, year = {2024}, type= {article}, }
- Pamela H. W. Svensson, Lucas Schwob, Oscar GrÃ¥näs, Isaak Unger, Olle Björneholm, Nicusor Timneanu, Rebecka Lindblad, Anna-Lydia Vieli, Vicente Zamudio-Bayer, Martin Timm, Konstantin Hirsch, Carl Caleman, Marta Berholts, “Heavy element incorporation in nitroimidazole radiosensitizers: molecular-level insights into fragmentation dynamics” Phys. Chem. Chem. Phys., vol. 26, 2 (2024).[Bibtex]
@article{ author = {Pamela H. W. Svensson, Lucas Schwob, Oscar GrÃ¥näs, Isaak Unger, Olle Björneholm, Nicusor Timneanu, Rebecka Lindblad, Anna-Lydia Vieli, Vicente Zamudio-Bayer, Martin Timm, Konstantin Hirsch, Carl Caleman, Marta Berholts}, title = {Heavy element incorporation in nitroimidazole radiosensitizers: molecular-level insights into fragmentation dynamics}, journal = {Phys. Chem. Chem. Phys.}, volume = {26}, number = {2}, abstract = {The present study investigates the photofragmentation behavior of iodine-enhanced nitroimidazole-based radiosensitizer model compounds in their protonated form using near-edge X-ray absorption mass spectrometry and quantum mechanical calculations. These molecules possess dual functionality: improved photoabsorption capabilities and the ability to generate species that are relevant to cancer sensitization upon photofragmentation. Four samples were investigated by scanning the generated fragments in the energy regions around C 1s{,} N 1s{,} O 1s{,} and I 3d-edges with a particular focus on NO2+ production. The experimental summed ion yield spectra are explained using the theoretical near-edge X-ray absorption fine structure spectrum based on density functional theory. Born–Oppenheimer-based molecular dynamics simulations were performed to investigate the fragmentation processes.}, year = {2024}, type= {article}, }
- Marcin Buchowiecki, Péter Szabó, “Transport Cross Sections and Collision Integrals for O(3P)-O(3P) Interaction” Plasma Chemistry and Plasma Processing, vol. 44, (2024).[Bibtex]
@article{ author = {Marcin Buchowiecki, Péter Szabó}, title = {Transport Cross Sections and Collision Integrals for O(3P)-O(3P) Interaction}, journal = {Plasma Chemistry and Plasma Processing}, volume = {44}, number = {}, abstract = {New collision integrals and transport cross sections for O( $$^{3}$$ 3 P)–O( $$^{3}$$ 3 P) interaction are reported in the 300–30000 K range. Those values are based on a new set of potential energy curves (PECs) calculated with the multireference configuration interaction method. The results of the classical and semiclassical WKB (Wentzel–Kramers–Brillouin) methods are compared, excellent performance of the classical approach is shown (discrepancy much lower than 1% even at room temperature). In particular, the classical and WKB methods agree very well for the repulsive potentials effectively reducing overall uncertainty.}, year = {2024}, type= {article}, }
- Barbora Kocábková, Jozef ÄŽurana, Jozef Rakovský, Andrij Pysanenko, Juraj Fedor, Milan Oncák, Michal FárnÃk, “Electron-triggered processes in halogenated carboxylates: dissociation pathways in CF3COCl and its clusters” Phys. Chem. Chem. Phys., vol. 26, 6 (2024).[Bibtex]
@article{ author = {Barbora Kocábková, Jozef ÄŽurana, Jozef Rakovský, Andrij Pysanenko, Juraj Fedor, Milan Oncák, Michal FárnÃk}, title = {Electron-triggered processes in halogenated carboxylates: dissociation pathways in CF3COCl and its clusters}, journal = {Phys. Chem. Chem. Phys.}, volume = {26}, number = {6}, abstract = {Trifluoroacetyl chloride{,} CF3COCl{,} is produced in the Earth{'}s atmosphere by photooxidative degradation of hydrochlorofluorocarbons{,} and represents a potential source of highly reactive halogen radicals. Despite considerable insight into photochemistry of CF3COCl{,} its reactivity towards electrons has not been addressed so far. We investigate the electron ionization and attachment in isolated CF3COCl molecules and (CF3COCl)N{,} max. N ≥ 10{,} clusters using a molecular beam experiment in combination with quantum chemical calculations. The ionization of the molecule at 70 eV electron energy leads to strong fragmentation: weakening of the C–C bond yields the CF3+ and COCl+ ions{,} while the fission of the C–Cl bond produces the major CF3CO+ fragment ion. The cluster spectra are dominated by Mn·COCl+ and Mn·CF3CO+ ions (M = CF3COCl). The electron attachment at energies between 1.5 and 11 eV also leads to the dissociation of the molecule breaking either the C–Cl bond at low energies below 3 eV yielding mainly Cl− ions{,} or dissociating the C–C bond at higher energies above 4 eV leading mainly to CF3− ions. In the clusters{,} the intact Mn− ions are stabilized after electron attachment at low energies with contribution of Mn·Cl− fragment ions. At higher energies{,} the Mn·Cl− fragments dominate the spectra{,} and C–C bond dissociation occurs as well yielding Mn·CF3−. Interestingly{,} Mn·Cl2− ions appear in the spectra at higher energies. We briefly discuss possible atmospheric implications.}, year = {2024}, type= {article}, }
- Alon Bogot and Mathias Poline and MingChao Ji and Arnaud Dochain and Ansgar Simonsson and Stefan Rosén and Henning Zettergren and Henning T. Schmidt and Richard D. Thomas and Daniel Strasser, “The mutual neutralization of hydronium and hydroxide” Science, vol. 383, 6680 (2024).[Bibtex]
@article{ author = {Alon Bogot and Mathias Poline and MingChao Ji and Arnaud Dochain and Ansgar Simonsson and Stefan Rosén and Henning Zettergren and Henning T. Schmidt and Richard D. Thomas and Daniel Strasser}, title = {The mutual neutralization of hydronium and hydroxide}, journal = {Science}, volume = {383}, number = {6680}, abstract = {Mutual neutralization of hydronium (H3O+) and hydroxide (OH−) ions is a very fundamental chemical reaction. Yet, there is only limited experimental evidence about the underlying reaction mechanisms. Here, we report three-dimensional imaging of coincident neutral products of mutual-neutralization reactions at low collision energies of cold and isolated ions in the cryogenic double electrostatic ion-beam storage ring (DESIREE). We identified predominant H2O + OH + H and 2OH + H2 product channels and attributed them to an electron-transfer mechanism, whereas a minor contribution of H2O + H2O with high internal excitation was attributed to proton transfer. The reported mechanism-resolved internal product excitation, as well as collision-energy and initial ion-temperature dependence, provide a benchmark for modeling charge-transfer mechanisms. The mutual neutralization of the hydronium cation and hydroxide anion to form neutral water molecules is one of the most basic chemical processes. It therefore has attracted considerable interest, but direct experimental probing of the underlying reaction mechanisms has been lacking. By realizing the interaction in merged beams of two ionic species with near-zero relative velocity, Bogot et al. directly visualized the neutral products of these reactions and reported three different product channels. Two channels were attributed to a predominant electron-transfer mechanism, and a smaller channel was associated with proton transfer. The two-beam collision experiment is an important step toward understanding the quantum dynamics of this fundamental reaction. —Yury Suleymanov Mutual neutralization measurements of isolated H3O+ and OH− ions revealed competing electron- and proton-transfer mechanisms.}, year = {2024}, type= {article}, }
- T. Kuraoka, S. Goto, M. Kanno, S. DÃaz-Tendero, J. Reino-González, F. Trinter, A. Pier, L. Sommerlad, N. Melzer, O. D. McGinnis, J. Kruse, T. Wenzel, T. Jahnke, H. Xue, N. Kishimoto, K. Yoshikawa, Y. Tamura, F. Ota, K. Hatada, K. Ueda, F. MartÃn, “Tracing Photoinduced Hydrogen Migration in Alcohol Dications from Time-Resolved Molecular-Frame Photoelectron Angular Distributions” The Journal of Physical Chemistry A, vol. 128, 7 (2024).[Bibtex]
@article{ author = {T. Kuraoka, S. Goto, M. Kanno, S. DÃaz-Tendero, J. Reino-González, F. Trinter, A. Pier, L. Sommerlad, N. Melzer, O. D. McGinnis, J. Kruse, T. Wenzel, T. Jahnke, H. Xue, N. Kishimoto, K. Yoshikawa, Y. Tamura, F. Ota, K. Hatada, K. Ueda, F. MartÃn}, title = {Tracing Photoinduced Hydrogen Migration in Alcohol Dications from Time-Resolved Molecular-Frame Photoelectron Angular Distributions}, journal = {The Journal of Physical Chemistry A}, volume = {128}, number = {7}, abstract = {The recent implementation of attosecond and few-femtosecond X-ray pump/X-ray probe schemes in large-scale free-electron laser facilities has opened the way to visualize fast nuclear dynamics in molecules with unprecedented temporal and spatial resolution. Here, we present the results of theoretical calculations showing how polarization-averaged molecular-frame photoelectron angular distributions (PA-MFPADs) can be used to visualize the dynamics of hydrogen migration in methanol, ethanol, propanol, and isopropyl alcohol dications generated by X-ray irradiation of the corresponding neutral species. We show that changes in the PA-MFPADs with the pump–probe delay as a result of intramolecular photoelectron diffraction carry information on the dynamics of hydrogen migration in real space. Although visualization of this dynamics is more straightforward in the smaller systems, methanol and ethanol, one can still recognize the signature of that motion in propanol and isopropyl alcohol and assign a tentative path to it. A possible pathway for a corresponding experiment requires an angularly resolved detection of photoelectrons in coincidence with molecular fragment ions used to define a molecular frame of reference. Such studies have become, in principle, possible since the first XFELs with sufficiently high repetition rates have emerged. To further support our findings, we provide experimental evidence of H migration in ethanol−OD from ion–ion coincidence measurements performed with synchrotron radiation.}, year = {2024}, type= {article}, }
- Vincent Richardson, Miroslav Polášek, Claire Romanzin, Paolo Tosi, Roland Thissen, Christian Alcaraz, Ján Žabka, Daniela Ascenzi , “Reactivity of the Ethenium Cation (C2H5+) with Ethyne (C2H2): A Combined Experimental and Theoretical Study” Molecules, vol. 29, 4 (2024).[Bibtex]
@article{ author = {Vincent Richardson, Miroslav Polášek, Claire Romanzin, Paolo Tosi, Roland Thissen, Christian Alcaraz, Ján Žabka, Daniela Ascenzi }, title = {Reactivity of the Ethenium Cation (C2H5+) with Ethyne (C2H2): A Combined Experimental and Theoretical Study}, journal = {Molecules}, volume = {29}, number = {4}, abstract = {The gas-phase reaction between the ethyl cation (C2H5+) and ethyne (C2H2) is re-investigated by measuring absolute reactive cross sections (CSs) and branching ratios (BRs) as a function of collision energy, in the thermal and hyperthermal energy range, via tandem-guided ion beam mass spectrometry under single collision conditions. Dissociative photoionization of C2H5Br using tuneable VUV radiation in the range 10.5–14.0 eV is employed to generate C2H5+, which has also allowed us to explore the impact of increasing (vibrational) excitation on the reactivity. Reactivity experiments are complemented by theoretical calculations, at the G4 level of theory, of the relative energies and structures of the most relevant stationary points on the reactive potential energy hypersurface (PES) and by mass-analyzed ion kinetic energy (MIKE) spectrometry experiments to probe the metastable decomposition from the [C4H7]+ PES and elucidate the underlying reaction mechanisms. Two main product channels have been identified at a centre-of-mass collision energy of ∼0.1 eV: (a) C3H3++CH4, with BR = 0.76±0.05 and (b) C4H5++H2, with BR = 0.22±0.02. A third channel giving C2H3+ in association with C2H4 is shown to emerge at both high internal excitation of C2H5+ and high collision energies. From CS measurements, energy-dependent total rate constants in the range 4.3×10−11−5.2×10−10 cm3·molecule−1·s−1 have been obtained. Theoretical calculations indicate that both channels stem from a common covalently bound intermediate, CH3CH2CHCH+, from which barrierless and exothermic pathways exist for the production of both cyclic c−C3H3+ and linear H2CCCH+ isomers of the main product channel. For the minor C4H5+ product, two isomers are energetically accessible: the three-member cyclic isomer c−C3H2(CH3)+ and the higher energy linear structure CH2CHCCH2+, but their formation requires multiple isomerization steps and passages via transition states lying only 0.11 eV below the reagents’ energy, thus explaining the smaller BR. Results have implications for the modeling of hydrocarbon chemistry in the interstellar medium and the atmospheres of planets and satellites as well as in laboratory plasmas (e.g., plasma-enhanced chemical vapor deposition of carbon nanotubes and diamond-like carbon films).}, year = {2024}, type= {article}, }
- Barbora Sedmidubská, Jaroslav KociÅ¡ek , “Interaction of low-energy electrons with radiosensitizers” Phys. Chem. Chem. Phys., vol. 26, 12 (2024).[Bibtex]
@article{ author = {Barbora Sedmidubská, Jaroslav Kocišek }, title = {Interaction of low-energy electrons with radiosensitizers}, journal = {Phys. Chem. Chem. Phys.}, volume = {26}, number = {12}, abstract = {We provide an experimentalist{'}s perspective on the present state-of-the-art in the studies of low-energy electron interactions with common radiosensitizers{,} including compounds used in combined chemo-radiation therapy and their model systems. Low-energy electrons are important secondary species formed during the interaction of ionizing radiation with matter. Their role in the radiation chemistry of living organisms has become an important topic for more than 20 years. With the increasing number of works and reviews in the field{,} we would like to focus here on a very narrow area of compounds that have been shown to have radio-sensitizing properties on the one hand{,} and high reactivity towards low-energy electrons on the other hand. Gas phase experiments studying electron attachment to isolated molecules and environmental effects on reaction dynamics are reviewed for modified DNA components{,} nitroimidazoles{,} and organometallics. In the end{,} we provide a perspective on the future directions that may be important for transferring the fundamental knowledge about the processes induced by low-energy electrons into practice in the field of rational design of agents for concomitant chemo-radiation therapy.}, year = {2024}, type= {article}, }
- Paulina Wierzbicka, Hassan Abdoul-Carime, Janina Kopyra, “Fragmentation of 5-fluorouridine induced by low energy (< 12 eV) electrons: insights into the radiosensitization of DNA” Phys. Chem. Chem. Phys., vol. 26, 11 (2024).[Bibtex]
@article{ author = {Paulina Wierzbicka, Hassan Abdoul-Carime, Janina Kopyra}, title = {Fragmentation of 5-fluorouridine induced by low energy (< 12 eV) electrons: insights into the radiosensitization of DNA}, journal = {Phys. Chem. Chem. Phys.}, volume = {26}, number = {11}, abstract = {5-Fluorouracil is now routinely used in chemo- and radiotherapy. Incorporated within DNA{,} the molecule is bound to the sugar backbone{,} forming the 5-fluorouridine sub-unit investigated in the present work. For the clinical usage of the latter{,} no information exists on the mechanisms that control the radiosensitizing effect at the molecular level. As low energy (< 12 eV) electrons are abundantly produced along the radiation tracks during cancer treatment using beams of high energy particles{,} we study how these ballistic secondary electrons damage the sensitizing molecule. The salient result from our study shows that the N-glycosidic bonds are principally affected with a cross-section of approximately two orders of magnitude higher than the canonical thymidine{,} reflecting to some degree the surviving factor of radiation-treated carcinoma cells with and without 5-fluorouracil incorporation. This result may help in the comprehension of the radiosensitizing effect of the fluoro-substituted thymidine in DNA.}, year = {2024}, type= {article}, }
- Miriam Kappe, Paul Martini, Arne Schiller, Elisabeth Gruber, Fabio Zappa, Serge A. Krasnokutski, Paul Scheier, and Michael Gatchell, “Spectroscopy of helium-tagged C60 anions” Phys. Rev. Res., vol. 6, 1 (2024).[Bibtex]
@article{ author = {Miriam Kappe, Paul Martini, Arne Schiller, Elisabeth Gruber, Fabio Zappa, Serge A. Krasnokutski, Paul Scheier, and Michael Gatchell}, title = {Spectroscopy of helium-tagged C60 anions}, journal = {Phys. Rev. Res.}, volume = {6}, number = {1}, abstract = {We present measurements of the electronic absorption spectrum of He-tagged buckminsterfullerene anions, C60−. Using a technique that allows for the efficient tagging of complex molecular anions with He, we achieve atomically resolved action spectra that provide an accurate determination of the gas-phase absorption spectrum in the near-infrared regime. In total we identify 27 absorption bands between 895 and 1057 nm.}, year = {2024}, type= {article}, }
- H. Abdoul-Carime, B. Lathuilière, P. Nedelec, J. Kopyra, “Synthesis of Benzene and Phenol From the Irradiation of Benzonitrile: Water Ices by (<10 eV) Electrons: Application to the Planets and Meteorites Surface Chemistry” Journal of Geophysical Research: Planets, vol. 129, 3 (2024).[Bibtex]
@article{ author = {H. Abdoul-Carime, B. Lathuilière, P. Nedelec, J. Kopyra}, title = {Synthesis of Benzene and Phenol From the Irradiation of Benzonitrile: Water Ices by (<10 eV) Electrons: Application to the Planets and Meteorites Surface Chemistry}, journal = {Journal of Geophysical Research: Planets}, volume = {129}, number = {3}, abstract = {Abstract Aromatic compounds are present in the interstellar space and on carbonaceous meteorites where they intriguingly represent the most important constituents along with the water ice. Exposed to the cosmic radiation, more complex species are generated via processes that are still far from being understood. The present study aims at studying the chemistry of benzonitrile in water ice environment when exposed to the ballistic low energy free electrons produced abundantly along the radiation tracks. Here we show that phenol and benzene are synthetized at the electron energy above but also below 6 eV via different routes, which can be selectively activated by tuning the electron energy. The reactivity presented in this work may contribute to a better understanding of the time evolution, via models and simulations, of species present in interstellar space ices and meteorites.}, year = {2024}, type= {article}, }
- Ana Isabel Lozano, Sarvesh Kumar, Pedro J. S. Pereira, Boutheïna Kerkeni, Gustavo GarcÃa, Paulo Limão-Vieira, “Low-lying Negative Ion States Probed in Potassium - Ethanol Collisions” ChemPhysChem}, vol. , (2024).[Bibtex]
@article{ author = {Ana Isabel Lozano, Sarvesh Kumar, Pedro J. S. Pereira, Boutheïna Kerkeni, Gustavo GarcÃa, Paulo Limão-Vieira}, title = {Low-lying Negative Ion States Probed in Potassium - Ethanol Collisions}, journal = {ChemPhysChem}}, volume = {}, number = {}, abstract = {Dissociative electron transfer in collisions between neutral potassium atoms and neutral ethanol molecules yields mainly OH−, followed by C2H5O−, O−, CH3− and CH2−. The dynamics of negative ions have been investigated by recording time-of-flight mass spectra in a wide range of collision energies from 17.5 to 350 eV in the lab frame, where the branching ratios show a relevant energy dependence for low/intermediate collision energies. The dominant fragmentation channel in the whole energy range investigated has been assigned to the hydroxyl anion in contrast to oxygen anion from dissociative electron attachment (DEA) experiments. This result shows the relevant role of the electron donor in the vicinity of the temporary negative ion formed allowing access to reactions which are not thermodynamically attained in DEA experiments. The electronic state spectroscopy of such negative ions, was obtained from potassium cation energy loss spectra in the forward scattering direction at 205 eV impact energy, showing a prevalent Feshbach resonance at 9.36±0.10 eV with mathematical equation character, while a less pronounced mathematical equation contribution assigned to a shape resonance has been obtained at 3.16±0.10 eV. Quantum chemical calculations for the lowest-lying unoccupied molecular orbitals in the presence of a potassium atom have been performed to support the experimental findings.}, year = {2024}, type= {article}, }
- Lara MartÃnez-Fernández, MiloÅ¡ Lj. Ranković, Francis Canon, Laurent Nahon, Alexandre Giuliani, Aleksandar R. Milosavljević, Ana Martin-Somer, “Photodissociation of leucine-enkephalin protonated peptide: an experimental and theoretical perspective” RSC Adv., vol. 14, 24 (2024).[Bibtex]
@article{ author = {Lara MartÃnez-Fernández, MiloÅ¡ Lj. Ranković, Francis Canon, Laurent Nahon, Alexandre Giuliani, Aleksandar R. Milosavljević, Ana Martin-Somer}, title = {Photodissociation of leucine-enkephalin protonated peptide: an experimental and theoretical perspective}, journal = {RSC Adv.}, volume = {14}, number = {24}, abstract = {Understanding the competing processes that govern far ultraviolet photodissociation (FUV-PD) of biopolymers such as proteins is a challenge. Here{,} we report a combined experimental and theoretical investigation of FUV-PD of protonated leucine-enkephalin pentapeptide ([YGGFL + H]+) in the gas-phase. Time-dependent density functional theory (TD-DFT) calculations in combination with experiments and previous results for amino acids and shorter peptides help in rationalizing the evolution of the excited states. The results confirm that fragmentation of [YGGFL + H]+ results mainly from vibrationally excited species in the ground electronic state{,} populated after internal conversion. We also propose fragmentation mechanisms for specific photo-fragments such as tyrosine side chain loss (with an extra hydrogen) or hydrogen loss. In general{,} we observe the same mechanisms as for smaller peptides or protonated Tyr and Phe{,} that are not quenched by the presence of other amino acids. Nevertheless{,} we also found some differences{,} as for H loss{,} in part due to the fact that the charge is solvated by the peptide chain and not only by the COOH terminal group.}, year = {2024}, type= {article}, }
- Alice F. Schmidt-May, Paul S. Barklem, Jon Grumer, Anish M. Amarsi, Mikael Björkhage, Mikael Blom, Arnaud Dochain, MingChao Ji, Paul Martini, Peter Reinhed, Stefan Rosén, Ansgar Simonsson, Henning Zettergren, Henrik Cederquist, and Henning T. Schmidt, “State-resolved mutual neutralization of 16O+ with 1H - and 2H - at collision energies below 100 meV” Phys. Rev. A}, vol. 109, 5 (2024).[Bibtex]
@article{ author = {Alice F. Schmidt-May, Paul S. Barklem, Jon Grumer, Anish M. Amarsi, Mikael Björkhage, Mikael Blom, Arnaud Dochain, MingChao Ji, Paul Martini, Peter Reinhed, Stefan Rosén, Ansgar Simonsson, Henning Zettergren, Henrik Cederquist, and Henning T. Schmidt}, title = {State-resolved mutual neutralization of 16O+ with 1H - and 2H - at collision energies below 100 meV}, journal = {Phys. Rev. A}}, volume = {109}, number = {5}, abstract = {We measured the product-state distribution and its dependence on the hydrogen isotope for the mutual neutralization between 16O+ and 1,2H− at the double electrostatic ion-beam storage ring DESIREE for center-of-mass collision energies below 100 meV. We find at least six product channels into ground-state hydrogen and oxygen in different excited states. The majority of oxygen products populate terms corresponding to 2𝑠22𝑝3(4𝑆∘)4𝑠 with 5S∘ as the main reaction product. We also observe product channels into terms corresponding to 2𝑠22𝑝3(4𝑆)3𝑝. Collisions with the heavier hydrogen isotope yield a branching into these lower excited states smaller than collisions with 1H−. The observed reaction products agree with the theoretical predictions. The detailed branching fractions, however, differ between the theoretical results, and none of them fully agree with the experiment.}, year = {2024}, type= {article}, }
- E. Bandeira, S. Kumar, A.I. Lozano, M.H.F. Bettega, S.V. Hoffmann, N.C. Jones, A. Souza Barbosa, P. Limão-Vieira , “Valence and Rydberg excitations of 3-fluorotoluene in the 4.4-10.8 eV photoabsorption energy region” Journal of Quantitative Spectroscopy and Radiative Transfer, vol. 312, (2024).[Bibtex]
@article{ author = {E. Bandeira, S. Kumar, A.I. Lozano, M.H.F. Bettega, S.V. Hoffmann, N.C. Jones, A. Souza Barbosa, P. Limão-Vieira }, title = {Valence and Rydberg excitations of 3-fluorotoluene in the 4.4-10.8 eV photoabsorption energy region}, journal = {Journal of Quantitative Spectroscopy and Radiative Transfer}, volume = {312}, number = {}, abstract = {The absolute photoabsorption cross sections for 3-fluorotoluene in the 4.4–10.8 eV energy-range were obtained for the first-time using a synchrotron radiation light source. New theoretical calculations, providing vertical excitation energies and oscillator strengths, were performed at the time-dependent density functional theory and the equation-of-motion coupled cluster method restricted to single and double excitations to qualitatively support the experimental data. The electronic transitions discernible in the photoabsorption spectrum have been assigned to valence, mixed valence-Rydberg and Rydberg transitions. Additionally, a comprehensive assignment of the vibronic structure was performed with the main contribution of C–H in plane bending mode progressions dictating the spectroscopy of the lowest-lying absorption band. From the absolute photoabsorption cross sections, the photolysis lifetimes of 3-fluorotoluene in the Earth's atmosphere were also obtained.}, year = {2024}, type= {article}, }
- S. Kumar, D. Duflot, N.C. Jones, S.V. Hoffmann, P. Limão-Vieira , “Exploring the low-lying electronic states of C4H6OS isomers, dihydro-2(3H)-thiophenone and dihydro-3(2H)-thiophenone” Journal of Quantitative Spectroscopy and Radiative Transfer, vol. 317, (2024).[Bibtex]
@article{ author = {S. Kumar, D. Duflot, N.C. Jones, S.V. Hoffmann, P. Limão-Vieira }, title = {Exploring the low-lying electronic states of C4H6OS isomers, dihydro-2(3H)-thiophenone and dihydro-3(2H)-thiophenone}, journal = {Journal of Quantitative Spectroscopy and Radiative Transfer}, volume = {317}, number = {}, abstract = {Results of a detailed study on the electronic state spectroscopy of C4H6OS isomers, dihydro-2(3H)-thiophenone and dihydro-3(2H)-thiophenone, have been obtained from high-resolution vacuum ultraviolet photoabsorption experiments together with quantum chemical calculations. The absolute photoabsorption cross-sections in the 3.7–10.7 eV energy range were obtained at the AU-UV beam line, ASTRID2 synchrotron radiation facility. The absorption spectra exhibit features due to transitions into valence and Rydberg states, superimposed on vibrational fine structure which appear much weaker in the photoabsorption spectrum of dihydro-3(2H)-thiophenone. Assignments have been proposed for some of the absorption bands with the aid of ab initio calculations at the equation-of-motion coupled-cluster singles and doubles level (EOM-CCSD) providing vertical excitation energies and oscillator strengths. The nature of the transitions was assessed by visual inspection of the natural orbitals for each transition and the average values from the electronic radial spatial extents of the electronic cloud. A comparison between the vibrational structure observed in the experimental spectra suggests relevant CO stretching excitations for both molecules, with important CH2 twisting and rocking modes for dihydro-2(3H)-thiophenone and ring stretching modes for dihydro-3(2H)-thiophenone. Photolysis lifetimes from 0 up to 50 km altitude in the Earth's atmosphere for both chemical compounds have been estimated from the absolute photoabsorption cross-sections.}, year = {2024}, type= {article}, }
- Piero Ferrari, Alexander K. Lemmensb and Britta Redlicha , “Infrared bands of neutral gas-phase carbon clusters in a broad spectral range” Phys. Chem. Chem. Phys., vol. 26, 16 (2024).[Bibtex]
@article{ author = {Piero Ferrari, Alexander K. Lemmensb and Britta Redlicha }, title = {Infrared bands of neutral gas-phase carbon clusters in a broad spectral range}, journal = {Phys. Chem. Chem. Phys.}, volume = {26}, number = {16}, abstract = {The identification of species in the interstellar medium requires precise and molecule-specific spectroscopic information in the laboratory framework{,} in broad spectral ranges and under conditions relevant to interstellar environments. In this work{,} we measure the gas-phase infrared spectra of neutral carbon clusters{,} CN (N = 6–11){,} in a molecular beam. The CN distribution is formed by photofragmentation of C60 molecules{,} concurrently showing a top-down formation mechanism. A broad spectral range in the infrared between 500–3200 cm−1 (20–3.125 μm) is investigated. We observe strong bands between 5 and 6 μm{,} in conjunction with novel features in the 3 μm region. Density functional theory calculations reveal that these short wavelength modes correspond to combination bands with significant infrared intensity. Moreover{,} we identify the N ≤ 10 clusters as linear{,} while C11 adopts a ring configuration{,} placing the linear-to-ring transition at N = 11 under our molecular beam conditions. The linearity of C10 is discussed based on the formation pathway from larger clusters in energetic conditions. Given the vast and very precise infrared information already been released from the James Webb Space Telescope mission{,} this infrared spectroscopic data set in conjunction with information on formation mechanisms is of major relevance for identifying neutral carbon clusters in astronomical environments.}, year = {2024}, type= {article}, }
- Károly TÅ‘kési, Robert D DuBois , “Ionization Cross Sections of Hydrogen Molecule by Electron and Positron Impact ” International Journal of Molecular Sciences, vol. 25, 6 (2024).[Bibtex]
@article{ author = {Károly Tőkési, Robert D DuBois }, title = {Ionization Cross Sections of Hydrogen Molecule by Electron and Positron Impact }, journal = {International Journal of Molecular Sciences}, volume = {25}, number = {6}, abstract = {We present ionization cross sections of hydrogen molecules by electron and positron impact for impact energies between 20 and 1000 eV. A three-body Classical Trajectory Monte Carlo approximation is applied to mimic the collision system. In this approach, the H2 molecule is modeled by a hydrogen-type atom with one active electron bound to a central core of effective charge with an effective binding energy. Although this model is crude for describing a hydrogen molecule, we found that the total cross sections for positron impact agree reasonably well with the experimental data. For the electron impact, our calculated cross sections are in good agreement with the experimental data in impact energies between 80 eV and 400 eV but are smaller at higher impact energies and larger at lower impact energies. Our calculated cross sections are compared with the scaled cross sections obtained experimentally for an atomic hydrogen target. We also present single differential cross sections as a function of the energy and angle of the ejected electron and scattered projectiles for a 250 eV impact. These are shown to agree well with available data. Impact parameter distributions are also compared for several impact energies.}, year = {2024}, type= {article}, }
- MarÃa Judit Montes de Oca-Estévez, Ã…lvaro Valdés and Rita Prosmiti , “A kernel-based machine learning potential and quantum vibrational state analysis of the cationic Ar hydride (Ar2H+)” Phys. Chem. Chem. Phys., vol. 26, 8 (2024).[Bibtex]
@article{ author = {MarÃa Judit Montes de Oca-Estévez, Ã…lvaro Valdés and Rita Prosmiti }, title = {A kernel-based machine learning potential and quantum vibrational state analysis of the cationic Ar hydride (Ar2H+)}, journal = {Phys. Chem. Chem. Phys.}, volume = {26}, number = {8}, abstract = {One of the most fascinating discoveries in recent years{,} in the cold and low pressure regions of the universe{,} was the detection of ArH+ and HeH+ species. The identification of such noble gas-containing molecules in space is the key to understanding noble gas chemistry. In the present work{,} we discuss the possibility of [Ar2H]+ existence as a potentially detectable molecule in the interstellar medium{,} providing new data on possible astronomical pathways and energetics of this compound. As a first step{,} a data-driven approach is proposed to construct a full 3D machine-learning potential energy surface (ML-PES) via the reproducing kernel Hilbert space (RKHS) method. The training and testing data sets are generated from CCSD(T)/CBS[56] computations{,} while a validation protocol is introduced to ensure the quality of the potential. In turn{,} the resulting ML-PES is employed to compute vibrational levels and molecular spectroscopic constants for the cation. In this way{,} the most common isotopologue in ISM{,} [36Ar2H]+{,} was characterized for the first time{,} while simultaneously{,} comparisons with previously reported values available for [40Ar2H]+ are discussed. Our present data could serve as a benchmark for future studies on this system{,} as well as on higher-order cationic Ar-hydrides of astrophysical interest.}, year = {2024}, type= {article}, }
- Veljko Vujcic, Bratislav P. Marinkovic, Vladimir A. Sreckovic, Sanja Tosic Darko Jevremovic, Ljubinko M. Ignjatovic, Maja S. Rabasovic, Dragutin Sevic, Nenad Simonovic and Nigel J. Masonc , “Current stage and future development of Belgrade collisional and radiative databases/datasets of importance for molecular dynamics ” Physical Chemistry Chemical Physics, vol. , (2023).[Bibtex]
@article{ author = {Veljko Vujcic, Bratislav P. Marinkovic, Vladimir A. Sreckovic, Sanja Tosic Darko Jevremovic, Ljubinko M. Ignjatovic, Maja S. Rabasovic, Dragutin Sevic, Nenad Simonovic and Nigel J. Masonc }, title = {Current stage and future development of Belgrade collisional and radiative databases/datasets of importance for molecular dynamics }, journal = {Physical Chemistry Chemical Physics}, volume = {}, number = {}, abstract = {}, year = {2023}, type= {Article}, }
- Ori Licht, Dario Barreiro-Lage, Patrick Rousseau, Alexandre Giuliani, Aleksandar R. Milosavljevic, Avinoam Isaak, Yitzhak Mastai, Amnon Albeck, Raj Singh, Vy T. T. Nguyen, Laurent Nahon, Lara Martinez-Fernandez, Sergio Diaz-Tendero, Yoni Toker, “Peptide Bond Formation in the Protonated Serine Dimer Following Vacuum UV Photon-Induced Excitation” Angewandte Chemie, vol. 135, 15 (2023).[Bibtex]
@article{ author = {Ori Licht, Dario Barreiro-Lage, Patrick Rousseau, Alexandre Giuliani, Aleksandar R. Milosavljevic, Avinoam Isaak, Yitzhak Mastai, Amnon Albeck, Raj Singh, Vy T. T. Nguyen, Laurent Nahon, Lara Martinez-Fernandez, Sergio Diaz-Tendero, Yoni Toker}, title = {Peptide Bond Formation in the Protonated Serine Dimer Following Vacuum UV Photon-Induced Excitation}, journal = {Angewandte Chemie}, volume = {135}, number = {15}, abstract = {}, year = {2023}, type= {Article}, }
- Ljubinko M. Ignjatovic, Vladimir A. Sreckovic, Milan S. Dimitrijevic, Desanka M. Sulic, “The radiative processes involving ion-atom alkali systems: The case of hydrogen and potassium” Advances in Space Research, vol. , (2023).[Bibtex]
@article{ author = {Ljubinko M. Ignjatovic, Vladimir A. Sreckovic, Milan S. Dimitrijevic, Desanka M. Sulic}, title = {The radiative processes involving ion-atom alkali systems: The case of hydrogen and potassium}, journal = {Advances in Space Research}, volume = {}, number = {}, abstract = {}, year = {2023}, type= {Article}, }
- Sarvesh Kumar, Denis Duflot, N Jones, S Hoffmann, Gustavo Garcia, Paulo Limão-Vieira, “The electronic structure of 2(5H)-thiophenone investigated by vacuum ultraviolet synchrotron radiation and theoretical calculations” The European Physical Journal D, vol. 77, (2024).[Bibtex]
@article{ author = { Sarvesh Kumar, Denis Duflot, N Jones, S Hoffmann, Gustavo Garcia, Paulo Limão-Vieira}, title = {The electronic structure of 2(5H)-thiophenone investigated by vacuum ultraviolet synchrotron radiation and theoretical calculations}, journal = {The European Physical Journal D}, volume = {77}, number = {}, abstract = {The electronic state spectroscopy of 2(5H)-thiophenone, C 4 H 4 OS, has been investigated by high-resolution vacuum ultraviolet photoabsorption in the 3.76–10.69 eV energy range using synchrotron radiation, together with novel quantum chemical calculations performed at the equation of motion coupled cluster singles and doubles (EOM-CCSD) level of theory. The major electronic transitions have been assigned to valence and Rydberg character, with relevant C=O, C=C and C–C stretching vibrations across the entire absorption spectrum. Photolysis lifetimes in the Earth’s atmosphere (0–50 km altitude) have been estimated from the absolute photoabsorption cross-sections, indicating that solar photolysis can be expected to be a strong sink mechanism. Graphical abstract}, year = {2024}, type= {article}, }
- Piero Ferrari, Klavs Hansen, Ozan Lacinbala, Ewald Janssens, Peter Lievens, “Fragmentation channels of non-fullerene cationic carbon clusters” Phys. Chem. Chem. Phys., vol. 25, 45 (2024).[Bibtex]
@article{ author = {Piero Ferrari, Klavs Hansen, Ozan Lacinbala, Ewald Janssens, Peter Lievens}, title = {Fragmentation channels of non-fullerene cationic carbon clusters}, journal = {Phys. Chem. Chem. Phys.}, volume = {25}, number = {45}, abstract = {The unimolecular fragmentation channels of highly excited small cationic carbon clusters have been measured with a time-of-flight mass spectrometer after photofragmentation. The dominant channel is loss of the neutral trimer{,} for all CN+N = 10–27 clusters except for N = 11{,} 12 which decay by monomer emission{,} and C25+ which shows competing loss of C2 and C3. The results permit to quantify the role of the rotational entropy in the competition between monomer and trimer decays with the help of energies calculated with density functional theory.}, year = {2024}, type= {article}, }
- Ori Licht, Maria Nihamkin, Mirit Anaby, Patrick Rousseau, Alexandre Giuliani, Aleksandar R Milosavljević, Raj Singh, Vy T T Nguyen, Laurent Nahon, Yoni Toker, “Vacuum UV studies of protonated serine clusters” Journal of Physics B: Atomic, Molecular and Optical Physics, vol. 56, 20 (2024).[Bibtex]
@article{ author = {Ori Licht, Maria Nihamkin, Mirit Anaby, Patrick Rousseau, Alexandre Giuliani, Aleksandar R Milosavljević, Raj Singh, Vy T T Nguyen, Laurent Nahon, Yoni Toker}, title = {Vacuum UV studies of protonated serine clusters}, journal = {Journal of Physics B: Atomic, Molecular and Optical Physics}, volume = {56}, number = {20}, abstract = {In a recent work, we have shown that photon absorption can cause a chemical bond to be created between the two monomers within a protonated serine dimer, a process known as intra-cluster bond formation, despite this process not occurring following thermal excitation via low energy collision-induced dissociation (LE-CID). Here we show further evidence for non-statistical photon-induced dissociation (PID) of the protonated serine dimer. In addition we discuss LE-CID and PID studies of the protonated serine octamer, showing that in this case as well, PID leads to non-statistical fragmentation and to the formation of two bonds between three neighboring monomers.}, year = {2024}, type= {article}, }
- Daniela Ascenzi, Ewa Erdmann, Paola Bolognesi, Lorenzo Avaldi, Mattea Carmen Castrovilli, Roland Thissen, Claire Romanzin, Christian Alcaraz, Ismanuel Rabadan, Luis Mendez, Sergio DÃaz-Tendero, Antonella Cartoni, , “H2O∙+ and OH+ reactivity versus furan: experimental low energy absolute cross sections for modeling radiation damage” Phys. Chem. Chem. Phys., vol. 25, 36 (2024).[Bibtex]
@article{ author = {Daniela Ascenzi, Ewa Erdmann, Paola Bolognesi, Lorenzo Avaldi, Mattea Carmen Castrovilli, Roland Thissen, Claire Romanzin, Christian Alcaraz, Ismanuel Rabadan, Luis Mendez, Sergio DÃaz-Tendero, Antonella Cartoni, }, title = {H2O∙+ and OH+ reactivity versus furan: experimental low energy absolute cross sections for modeling radiation damage}, journal = {Phys. Chem. Chem. Phys.}, volume = {25}, number = {36}, abstract = {Radiotherapy is one of the most widespread and efficient strategies to fight malignant tumors. Despite its broad application{,} the mechanisms of radiation-DNA interaction are still under investigation. Theoretical models to predict the effects of a particular delivered dose are still in their infancy due to the difficulty of simulating a real cell environment{,} as well as the inclusion of a large variety of secondary processes. This work reports the first experimental study of the ion–molecule reactions of the H2O˙+ and OH+ ions{,} produced by photoionization with synchrotron radiation{,} with a furan (c-C4H4O) molecule{,} a template for deoxyribose sugar in DNA. The present experiments{,} performed as a function of the collision energy of the ions and the tunable photoionization energy{,} provide key parameters for the theoretical modelling of the effect of radiation dose{,} like the absolute cross sections for producing protonated furan (furanH+) and a radical cation (furan˙+){,} the most abundant products{,} which can amount up to 200 Å2 at very low collision energies (<1.0 eV). The experimental results show that furanH+ is more fragile{,} indicating how the protonation of the sugar component of the DNA may favor its dissociation with possible major radiosensitizing effects. Moreover{,} the ring opening of furanH+ isomers and the potential energy surface of the most important fragmentation channels have been explored by molecular dynamics simulations and quantum chemistry calculations. The results show that{,} in the most stable isomer of furanH+{,} the ring opening occurs via a low energy pathway with carbon–oxygen bond cleavage{,} followed by the loss of neutral carbon monoxide and the formation of the allyl cation CH2CHCH2+{,} which instead is not observed in the fragmentation of furan˙+. At higher energies the ring opening through the carbon–carbon bond is accompanied by the loss of formaldehyde{,} producing HCCCH2+{,} the most intense fragment ion detected in the experiments. This work highlights the importance of the secondary processes{,} like the ion–molecule reactions at low energies in the radiation damage due to their very large cross sections{,} and it aims to provide benchmark data for the development of suitable models to approach this low collision energy range.}, year = {2024}, type= {article}, }
- Safa Kechoindi, Ben Yaghlane Saida, Terzi Neila, J. Palaudoux, Majdi Hochlaf, , “Characterization and photochemistry of XCO2 (X = F, NH2, CH3) radicals” The European Physical Journal Special Topics, vol. 232, (2024).[Bibtex]
@article{ author = {Safa Kechoindi, Ben Yaghlane Saida, Terzi Neila, J. Palaudoux, Majdi Hochlaf, }, title = {Characterization and photochemistry of XCO2 (X = F, NH2, CH3) radicals}, journal = {The European Physical Journal Special Topics}, volume = {232}, number = {}, abstract = {The XCO2 (X = F, NH2, CH3) radicals are present in the Earth atmosphere, where they are produced by the degradation of Volatile Organic Compounds (VOCs), either industrial or natural. Here, we use advanced ab initio methodologies to characterize these species in their ground and electronically excited states. Computations are carried out using the Coupled Clusters, both standard and explicitly correlated versions, and multiconfigurational approaches. Several basis sets were used. Afterward, the geometrical parameters and the total energies were extrapolated to the complete basis set (CBS) limit. We also mapped their potentials along the central bond to have insights on the XCO2 → X + CO2 reactions. We thus show that the ground and the lowest electronic excited states are long-lived, for which we provide a set of accurate structural and spectroscopic parameters. The upper electronic states are subject of unimolecular decompositions producing CO2 and X fragments. Our calculations show that the FCO2 (X2B2) → F(2P) + CO2 (X1Σg+) and the CH3CO2 (X2A″) → CH3(X2A″2) + CO2 (X1Σg+) processes require at least 3.5 eV energy to occur, while less energy (of ∼ 2.5 eV) is needed for the NH2CO2 (X2A″) → NH2(X2B1) + CO2 (X1Σg+) reaction. The present findings and data are useful to characterize these radicals in the laboratory, in planetary atmospheres and in combustion and to understand their physical chemistry there.}, year = {2024}, type= {article}, }
- Sarvesh Kumar, Masamitsu Hoshino, Boutheïna Kerkeni, Gustavo GarcÃa, Paulo Limão-Vieira, , “Isotope Effect in D2O Negative Ion Formation in Electron Transfer Experiments: DO - D Bond Dissociation Energy” The Journal of Physical Chemistry Letters, vol. 14, 23 (2024).[Bibtex]
@article{ author = {Sarvesh Kumar, Masamitsu Hoshino, Boutheïna Kerkeni, Gustavo GarcÃa, Paulo Limão-Vieira, }, title = {Isotope Effect in D2O Negative Ion Formation in Electron Transfer Experiments: DO - D Bond Dissociation Energy}, journal = {The Journal of Physical Chemistry Letters}, volume = {14}, number = {23}, abstract = {5362-5369}, year = {2024}, type= {article}, }
- Hassan Abdoul-Carime, Janina Kopyra, “Reactions in CCl4 films deposited onto a cold gold substrate induced by charge transfer vs (0-5) eV free electrons” Chemical Physics Letters, vol. 810, (2024).[Bibtex]
@article{ author = {Hassan Abdoul-Carime, Janina Kopyra}, title = {Reactions in CCl4 films deposited onto a cold gold substrate induced by charge transfer vs (0-5) eV free electrons}, journal = {Chemical Physics Letters}, volume = {810}, number = {}, abstract = {Reactions induced by electrons may arise from the charge transfer when molecules are deposited onto a metal substrate or from bombardment. Here, we comparatively study, by using the same experimental set-up, the reactions induced to carbon tetrachloride via the two processes. We found that free electrons bombardment with energy below 5 eV trigger the production of Cl2 as for the charge transfer reaction. From the present measurements, no formation of chlorocarbon chains from the irradiation of carbon tetrachloride films by electrons were observed at low energies.}, year = {2024}, type= {article}, }
- Michael Gatchell, Henning Zettergren, Klavs Hansen, , “The largest fullerene” Phys. Chem. Chem. Phys., vol. 25, 25 (2024).[Bibtex]
@article{ author = {Michael Gatchell, Henning Zettergren, Klavs Hansen, }, title = {The largest fullerene}, journal = {Phys. Chem. Chem. Phys.}, volume = {25}, number = {25}, abstract = {Fullerenes are lowest energy structures for gas phase all-carbon particles for a range of sizes, but graphite remains the lowest energy allotrope of bulk carbon. This implies that the lowest energy structure changes nature from fullerenes to graphite or graphene at some size and therefore, in turn, implies a limit on the size of free fullerenes as ground state structures. We calculate this largest stable single shell fullerene to be of size N = 1 × 104, using the AIREBO effective potential. Above this size fullerene onions are more stable, with an energy per atom that approaches graphite structures. Onions and graphite have very similar ground state energies, raising the intriguing possibility that fullerene onions could be the lowest free energy states of large carbon particles in some temperature range.}, year = {2024}, type= {article}, }
- José E. Navarro Navarrete, James N. Bull, Henrik Cederquist, Suvasthika Indrajith, MingChao Ji, Henning T. Schmidt, Henning Zettergren, Boxing Zhu, Mark H. Stockett, “Experimental radiative cooling rates of a polycyclic aromatic hydrocarbon cation” Faraday Discuss., vol. 245, 0 (2024).[Bibtex]
@article{ author = {José E. Navarro Navarrete, James N. Bull, Henrik Cederquist, Suvasthika Indrajith, MingChao Ji, Henning T. Schmidt, Henning Zettergren, Boxing Zhu, Mark H. Stockett}, title = {Experimental radiative cooling rates of a polycyclic aromatic hydrocarbon cation}, journal = {Faraday Discuss.}, volume = {245}, number = {0}, abstract = {Several small Polycyclic Aromatic Hydrocarbons (PAHs) have been identified recently in the Taurus Molecular Cloud (TMC-1) using radio telescope observations. Reproducing the observed abundances of these molecules has been a challenge for astrochemical models. Rapid radiative cooling of PAHs by Recurrent Fluorescence (RF){,} the emission of optical photons from thermally populated electronically excited states{,} has been shown to efficiently stabilize small PAHs following ionization{,} augmenting their resilience in astronomical environments and helping to rationalize their observed high abundances. Here{,} we use a novel method to experimentally determine the radiative cooling rate of the cation of 1-cyanonaphthalene (C10H7CN{,} 1-CNN){,} the neutral species of which has been identified in TMC-1. Laser-induced dissociation rates and kinetic energy release distributions of 1-CNN cations isolated in a cryogenic electrostatic ion-beam storage ring are analysed to track the time evolution of the vibrational energy distribution of the initially hot ion ensemble as it cools. The measured cooling rate is in good agreement with the previously calculated RF rate coefficient. Improved measurements and models of the RF mechanism are needed to interpret astronomical observations and refine predictions of the stabilities of interstellar PAHs.}, year = {2024}, type= {article}, }
- Z. Juhász, S. T. S. Kovács, V. Vizcaïno, P. Herczku, S. Demes, R. Rácz, B. Sulik, S. Biri, N. Sens, D. V. Mifsud, and J.-Y. Chesnel, “Molecular-rotation-induced splitting of the binary ridge in the velocity map of sub-eV H+ ions ejected from H2 molecules by ion impact” Phys. Rev. A, vol. 107, 1 (2024).[Bibtex]
@article{ author = {Z. Juhász, S. T. S. Kovács, V. Vizcaïno, P. Herczku, S. Demes, R. Rácz, B. Sulik, S. Biri, N. Sens, D. V. Mifsud, and J.-Y. Chesnel}, title = {Molecular-rotation-induced splitting of the binary ridge in the velocity map of sub-eV H+ ions ejected from H2 molecules by ion impact}, journal = {Phys. Rev. A}, volume = {107}, number = {1}, abstract = {In studies of ion-induced molecular fragmentation, the challenging measurement of the velocity distribution of fragments emitted below 1-eV kinetic energy is rarely achieved, although most fragments have an energy below this value. Here, we study H+ fragment emission in collisions of 10-keV O+ ions with H2 molecules using a field-free time-of-flight technique developed specifically to detect sub-eV fragments. We find that, in the velocity map, the binary ridge due to direct H+ knockout is split into two parts arising from the rotational motion of the H2 molecule, and that this split scales with rotational velocity. The velocity distribution of the nuclei in the original molecule is determined and the thermally populated 𝐽=1 rotational level is found to be the dominant contributor, although asymmetry in the split indicates projectile-induced rotational transitions between 𝑀 sublevels. These rotation effects influence fragment emission probabilities, thus carrying important consequences for the radiation-induced hydrogen loss and H2 dissociation in the atmospheres or exospheres of planets and moons.}, year = {2024}, type= {article}, }
- Smita Ganguly, Mathieu Gisselbrecht, Per Eng-Johnsson, Raimund Feifel, Sergio DÃaz-Tendero, Eva Muchová, Aleksandar R Milosavljević, Patrick Rousseau, Sylvain Maclot , “Resonant Inner-Shell Photofragmentation of Adamantane (C10H16)” Molecules, vol. 28, 14 (2024).[Bibtex]
@article{ author = {Smita Ganguly, Mathieu Gisselbrecht, Per Eng-Johnsson, Raimund Feifel, Sergio DÃaz-Tendero, Eva Muchová, Aleksandar R Milosavljević, Patrick Rousseau, Sylvain Maclot }, title = {Resonant Inner-Shell Photofragmentation of Adamantane (C10H16)}, journal = {Molecules}, volume = {28}, number = {14 }, abstract = {Adamantane, the smallest diamondoid molecule with a symmetrical cage, contains two distinct carbon sites, CH and CH2. The ionization/excitation of the molecule leads to the cage opening and strong structural reorganization. While theoretical predictions suggest that the carbon site CH primarily causes the cage opening, the role of the other CH2 site remains unclear. In this study, we used advanced experimental Auger electron–ion coincidence techniques and theoretical calculations to investigate the fragmentation dynamics of adamantane after resonant inner-shell photoexcitation. Our results demonstrate that some fragmentation channels exhibit site-sensitivity of the initial core–hole location, indicating that different carbon site excitations could lead to unique cage opening mechanisms.}, year = {2024}, type= {article}, }
- Yining Huo, Mónica K Espinoza Cangahuala, Vicente Zamudio-Bayer, Marcelo Goulart, Markus Kubin, Martin Timm, J Tobias Lau, Bernd von Issendorff, Ronnie Hoekstra, Shirin Faraji, Thomas Schlathölter, “An X-ray spectroscopy study of structural stability of superhydrogenated pyrene derivatives” Monthly Notices of the Royal Astronomical Society, vol. 523, 1 (2024).[Bibtex]
@article{ author = {Yining Huo, Mónica K Espinoza Cangahuala, Vicente Zamudio-Bayer, Marcelo Goulart, Markus Kubin, Martin Timm, J Tobias Lau, Bernd von Issendorff, Ronnie Hoekstra, Shirin Faraji, Thomas Schlathölter}, title = {An X-ray spectroscopy study of structural stability of superhydrogenated pyrene derivatives}, journal = {Monthly Notices of the Royal Astronomical Society}, volume = {523}, number = {1}, abstract = {The stability of polycyclic aromatic hydrocarbons (PAHs) upon soft X-ray absorption is of crucial relevance for PAH survival in X-ray dominated regions. PAH stability depends on molecular size but also on the degree of hydrogenation that is related to H2 formation in the interstellar medium. In this project, we intend to reveal the changes of electronic structure caused by hydrogenation and the impact of hydrogenation on the stability of the carbon backbone for cationic pyrene and its hydrogenated derivatives by analysis of near C K-edge soft X-ray photoions. In our experiments, the PAH cations were trapped in a cryogenic radiofrequency linear ion trap and exposed to monochromatic X-rays with energies from 279 to 300 eV. The photoproducts were mass-analysed by means of time-of-flight spectroscopy. Partial ion yields were then studied as a function of photon energy. X-ray absorption spectra computed by time-dependent density functional theory (TD-DFT) aided the interpretation of the experimental results. A very good agreement between experimental data and TD-DFT with short-range corrected functionals for all PAH ions was reached. The near-edge X-ray absorption mass spectra exhibit clear peaks due to C 1s transitions to singly occupied molecular orbitals and to low-lying unoccupied molecular orbitals. In contrast to coronene cations, where hydrogen attachment drastically increases photostability of coronene, the influence of hydrogenation on photostability is substantially weaker for pyrene cations. Here, hydrogen attachment even destabilizes the molecular structure. An astrophysical model describes the half-life of PAH ions in interstellar environments.}, year = {2024}, type= {article}, }
- J Boffelli, F Gauchet, D O Kashinski, D Talbi, A P Hickman, K Chakrabarti, E Bron, A Orbán, J Zs Mezei, I F Schneider, “Population of ground and lowest excited states of sulfur via the dissociative recombination of SH+ in the diffuse interstellar medium” Monthly Notices of the Royal Astronomical Society, vol. 522, 2 (2024).[Bibtex]
@article{ author = {J Boffelli, F Gauchet, D O Kashinski, D Talbi, A P Hickman, K Chakrabarti, E Bron, A Orbán, J Zs Mezei, I F Schneider}, title = {Population of ground and lowest excited states of sulfur via the dissociative recombination of SH+ in the diffuse interstellar medium}, journal = {Monthly Notices of the Royal Astronomical Society}, volume = {522}, number = {2}, abstract = {Our previous study on dissociative recombination of ground state SH+ through 2Π states of SH is extended by taking into account the contribution of 4Π states recently explored by quantum chemistry methods. Multichannel quantum defect theory is employed for the computation of cross sections and rate coefficients for dissociative recombination, but also for vibrational excitation. Furthermore, we produce the atomic yields resulting from recombination, quantifying the generation of sulfur atoms in their ground (3P) and lowest excited (1D) states, respectively.}, year = {2024}, type= {article}, }
- Enliang Wang, Nora G Kling, Aaron C LaForge, Razib Obaid, Shashank Pathak, Surjendu Bhattacharyya, Severin Meister, Florian Trost, Hannes Lindenblatt, Patrizia Schoch, Matthias Kübel, Thomas Pfeifer, Artem Rudenko, Sergio DÃaz-Tendero, Fernando MartÃn, Robert Moshammer, Daniel Rolles, Nora Berrah, “Ultrafast Roaming Mechanisms in Ethanol Probed by Intense Extreme Ultraviolet Free-Electron Laser Radiation: Electron Transfer versus Proton Transfer” The Journal of Physical Chemistry Letters, vol. 14, 18 (2024).[Bibtex]
@article{ author = {Enliang Wang, Nora G Kling, Aaron C LaForge, Razib Obaid, Shashank Pathak, Surjendu Bhattacharyya, Severin Meister, Florian Trost, Hannes Lindenblatt, Patrizia Schoch, Matthias Kübel, Thomas Pfeifer, Artem Rudenko, Sergio DÃaz-Tendero, Fernando MartÃn, Robert Moshammer, Daniel Rolles, Nora Berrah}, title = {Ultrafast Roaming Mechanisms in Ethanol Probed by Intense Extreme Ultraviolet Free-Electron Laser Radiation: Electron Transfer versus Proton Transfer}, journal = {The Journal of Physical Chemistry Letters}, volume = {14}, number = {18}, abstract = {Ultrafast H2+ and H3+ formation from ethanol is studied using pump-probe spectroscopy with an extreme ultraviolet (XUV) free-electron laser. The first pulse creates a dication, triggering H2 roaming that leads to H2+ and H3+ formation, which is disruptively probed by a second pulse. At photon energies of 28 and 32 eV, the ratio of H2+ to H3+ increases with time delay, while it is flat at a photon energy of 70 eV. The delay-dependent effect is ascribed to a competition between electron and proton transfer. High-level quantum chemistry calculations show a flat potential energy surface for H2 formation, indicating that the intermediate state may have a long lifetime. The ab initio molecular dynamics simulation confirms that, in addition to the direct emission, a small portion of H2 undergoes a roaming mechanism that leads to two competing pathways: electron transfer from H2 to C2H4O2+ and proton transfer from C2H4O2+ to H2.}, year = {2024}, type= {article}, }
- Jelena Tamuliene, Teodora Kirova, Liudmila Romanova, Vasyl Vukstich, Alexander Snegursky , “Fragmentation of tyrosine by high-energy electron impact” The European Physical Journal D, vol. 77, (2024).[Bibtex]
@article{ author = {Jelena Tamuliene, Teodora Kirova, Liudmila Romanova, Vasyl Vukstich, Alexander Snegursky }, title = {Fragmentation of tyrosine by high-energy electron impact}, journal = {The European Physical Journal D}, volume = {77}, number = {}, abstract = {The experimental mass spectra of the tyrosine molecule measured at different microtron accelerator-induced high-energy electron irradiation doses (i.e., 0, 5, and 20 kGy) have been identified and analyzed. The experimental investigation was carried out along with the theoretical study performed by Becke’s three-parameter hybrid density functional approach without and with the inclusion of electric and magnetic fields. It has been shown that high-energy (11.5 MeV) electrons cause irreversible changes in the structure and energy parameters of the molecule under study. The study revealed the importance of proton transfer for fragment formation of the irradiated and non-irradiated tyrosine. }, year = {2024}, type= {article}, }
- Teodora Kirova, Jelena Tamuliene , “Numerical Studies of the Impact of Electromagnetic Field of Radiation on Valine” Materials, vol. 16, 5 (2024).[Bibtex]
@article{ author = {Teodora Kirova, Jelena Tamuliene }, title = {Numerical Studies of the Impact of Electromagnetic Field of Radiation on Valine}, journal = {Materials}, volume = {16}, number = {5}, abstract = {We present the results of numerical calculations of the effect of an electromagnetic field of radiation on valine, and compare them to experimental results available in the literature. We specifically focus on the effects of a magnetic field of radiation, by introducing modified basis sets, which incorporate correction coefficients to the s-, p- or only the p-orbitals, following the method of anisotropic Gaussian-type orbitals. By comparing the bond length, angle, dihedral angles, and condense-to-atom-all electrons, obtained without and with the inclusion of dipole electric and magnetic fields, we concluded that, while the charge redistribution occurs due to the electric field influence, the changes in the dipole momentum projection onto the y- and z- axes are caused by the magnetic field. At the same time, the values of the dihedral angles could vary by up to 4 degrees, due to the magnetic field effects. We further show that taking into account the magnetic field in the fragmentation processes provides better fitting of the experimentally obtained spectra: thus, numerical calculations which include magnetic field effects can serve as a tool for better predictions, as well as for analysis of the experimental outcomes.}, year = {2024}, type= {article}, }
- Janina Kopyra and Hassan Abdoul-Carime, “Fragmentation of metal(II) bis(acetylacetonate) complexes induced by slow electrons” Beilstein Journal of Nanotechnology, vol. 14, (2024).[Bibtex]
@article{ author = {Janina Kopyra and Hassan Abdoul-Carime}, title = {Fragmentation of metal(II) bis(acetylacetonate) complexes induced by slow electrons}, journal = {Beilstein Journal of Nanotechnology}, volume = {14}, number = {}, abstract = {Nowadays, organometallic complexes receive particular attention because of their use in the design of pure nanoscale metal structures. In the present work, we present results obtained from a series of studies on the degradation of metal(II) bis(acetylacetonate)s induced by low-energy electrons. These slow particles induce the formation of the acetylacetonate anion, [acac]−, and the parent anion as the most dominant species at incident electron energies near 0 eV. They also fragment the organometallic compounds via various competitive reaction channels that occur at higher energies via dissociative electron attachment. The reported data may contribute to a better understanding of the physical chemistry underlying the electron–molecule interactions, which is crucial for potential applications of these molecular systems in the deposition of nanoscale structures.}, year = {2024}, type= {article}, }
- Vladimir A. Srećković and Ljubinko M. Ignjatović and Milan S. Dimitrijević and Veljko Vujcić and Miodrag Malović and Darko Jevremović and Nikolai N. Bezuglov and Andrey N. Klyucharev, “The Rydberg atom-atom collisions: Chemi-ionization cross-sections and rate coefficients in alkali-metal astrophysical and low-temperature laboratory plasmas” Advances in Space Research, vol. 71, 2 (2024).[Bibtex]
@article{ author = {Vladimir A. Srećković and Ljubinko M. Ignjatović and Milan S. Dimitrijević and Veljko Vujcić and Miodrag Malović and Darko Jevremović and Nikolai N. Bezuglov and Andrey N. Klyucharev}, title = {The Rydberg atom-atom collisions: Chemi-ionization cross-sections and rate coefficients in alkali-metal astrophysical and low-temperature laboratory plasmas}, journal = {Advances in Space Research}, volume = {71}, number = {2}, abstract = {In this manuscript, the chemi-ionization (CI) processes in atom - Rydberg atom collisions are examined. We obtained the cross-sections, as well as rate coefficients for CI processes in potassium and sodium collisions for principal quantum numbers 5⩽n⩽25 in the 500 K ⩽T⩽1500 K temperature region. The presented data could be useful for the improvement of analysis and modelling of weakly ionized layers of different atmospheres and cosmic objects where these and other CI processes could change excited state populations and the free electron density, consequently affecting the optical characteristics.}, year = {2024}, type= {article}, }
- A. GarcÃa-Abenza, A. I. Lozano, L. Alvarez, J. C. Oller, J. Rosado, F. Blanco, P. Limão-Vieira, G. GarcÃa, , “Evaluated electron scattering cross section dataset for gaseous benzene in the energy range 0.1-1000 eV” Phys. Chem. Chem. Phys., vol. 25, 30 (2024).[Bibtex]
@article{ author = {A. GarcÃa-Abenza, A. I. Lozano, L. Alvarez, J. C. Oller, J. Rosado, F. Blanco, P. Limão-Vieira, G. GarcÃa, }, title = {Evaluated electron scattering cross section dataset for gaseous benzene in the energy range 0.1-1000 eV}, journal = {Phys. Chem. Chem. Phys.}, volume = {25}, number = {30}, abstract = {In this study{,} a complete and self-consistent cross section dataset for electron transport simulations through gaseous benzene in the energy range 0.1–1000 eV has been critically compiled. Its reliability has been evaluated through a joint experimental and computational procedure. To accomplish this{,} the compiled dataset has been used as input for event-by-event Monte Carlo simulations of the magnetically confined electron transport through gaseous benzene{,} and the simulated transmitted intensity has been compared with the experimental one for different incident energies and benzene gas pressures.}, year = {2024}, type= {article}, }
- James N. Bull, Paola Bolognesi, Cate S. Anstöter, Eleanor K. Ashworth, José E. Navarro Navarrete, Boxing Zhu, Robert Richter, Nitish Pal, Jacopo Chiarinelli, Lorenzo Avaldi, Henning Zettergren, Mark H. Stockett, “Autoionization from the plasmon resonance in isolated 1-cyanonaphthalene” The Journal of Chemical Physics, vol. 158, 24 (2024).[Bibtex]
@article{ author = {James N. Bull, Paola Bolognesi, Cate S. Anstöter, Eleanor K. Ashworth, José E. Navarro Navarrete, Boxing Zhu, Robert Richter, Nitish Pal, Jacopo Chiarinelli, Lorenzo Avaldi, Henning Zettergren, Mark H. Stockett}, title = {Autoionization from the plasmon resonance in isolated 1-cyanonaphthalene}, journal = {The Journal of Chemical Physics}, volume = {158}, number = {24}, abstract = {Polycyclic aromatic hydrocarbons have widely been conjectured to be ubiquitous in space, as supported by the recent discovery of two isomers of cyanonaphthalene, indene, and 2-cyanoindene in the Taurus molecular cloud-1 using radioastronomy. Here, the photoionization dynamics of 1-cyanonaphthalene (1-CNN) are investigated using synchrotron radiation over the hν = 9.0–19.5 eV range, revealing that prompt autoionization from the plasmon resonance dominates the photophysics for hν = 11.5–16.0 eV. Minimal photo-induced dissociation, whether originating from an excited state impulsive bond rupture or through internal conversion followed by a statistical bond cleavage process, occurs over the microsecond timescale (as limited by the experimental setup). The direct photoionization cross section and photoelectron angular distributions are simulated using an ezDyson model combining Dyson orbitals with Coulomb wave photoejection. When considering these data in conjunction with recent radiative cooling measurements on 1-CNN+, which showed that cations formed with up to 5 eV of internal energy efficiently stabilize through recurrent fluorescence, we conclude that the organic backbone of 1-CNN is resilient to photodestruction by VUV and soft XUV radiation. These dynamics may prove to be a common feature for the survival of small polycyclic aromatic hydrocarbons in space, provided that the cations have a suitable electronic structure to support recurrent fluorescence.}, year = {2024}, type= {article}, }
- Maria Judit Montes de Oca-Estevez, Beatriz Darna, Borja Garcia-Ruiz, Rita Prosmiti, Tomas Gonzalez-Lezana, Debasish Koner , “Ar+ArH+ Reactive Collisions of Astrophysical Interest: The Case of 36Ar” ChemPhysChem, vol. 24, 20 (2024).[Bibtex]
@article{ author = {Maria Judit Montes de Oca-Estevez, Beatriz Darna, Borja Garcia-Ruiz, Rita Prosmiti, Tomas Gonzalez-Lezana, Debasish Koner }, title = {Ar+ArH+ Reactive Collisions of Astrophysical Interest: The Case of 36Ar}, journal = {ChemPhysChem}, volume = {24}, number = {20}, abstract = {Abstract The reactive collision between 36Ar and the 36ArH+ species has been investigated by means of quantum mechanical (QM), quasiclassical trajectories (QCT) and statistical quantum mechanical (SQM) approaches. Reaction probabilities, cross sections as a function of the energy and rate constants in terms of the temperature have been obtained. Cumulative distributions as a function of the collision time and the inspection of selected QCT corresponding to specific dynamical mechanisms have been analysed. Predictions by means of the SQM method are in good agreement with the QM results, thus supporting the complex-forming nature of the process.}, year = {2024}, type= {article}, }
- Yehuda Ben-Shabo, Adeliya Kurbanov, Claus Dieter Schröter, Robert Moshammer, Holger Kreckel, Yoni Toker, “Velocity map imaging with no spherical aberrations” Phys. Chem. Chem. Phys., vol. 25, 37 (2024).[Bibtex]
@article{ author = {Yehuda Ben-Shabo, Adeliya Kurbanov, Claus Dieter Schröter, Robert Moshammer, Holger Kreckel, Yoni Toker}, title = {Velocity map imaging with no spherical aberrations}, journal = {Phys. Chem. Chem. Phys.}, volume = {25}, number = {37}, abstract = {Velocity map imaging (VMI) is a powerful technique to deduce the kinetic energy of ions or electrons that are produced from a large volume in space with good resolution. The size of the acceptance volume is determined by the spherical aberrations of the ion optical system. Here we present an analytical derivation for velocity map imaging with no spherical aberrations. We will discuss a particular example for the implementation of the technique that allows using the reaction microscope recently installed in the cryogenic storage ring (CSR) in a VMI mode. SIMION simulations confirm that a beam of electrons produced almost over the entire volume of the source region{,} with a width of 8 cm{,} can be focused to a spot of 0.1 mm on the detector. The use of the same formalism for position imaging{,} as well as in a mixed mode where position imaging is in one axis and velocity map imaging is in a different axis{,} is also discussed.}, year = {2024}, type= {article}, }
- Yuri Bedjanian, Péter Szabó, György Lendvay, , “Experimental and Theoretical Study of the Kinetics of the CH3 + HBr -> CH4 + Br Reaction and the Temperature Dependence of the Activation Energy of CH4 + Br -> CH3 + HBr” The Journal of Physical Chemistry A, vol. 127, 33 (2024).[Bibtex]
@article{ author = {Yuri Bedjanian, Péter Szabó, György Lendvay, }, title = {Experimental and Theoretical Study of the Kinetics of the CH3 + HBr -> CH4 + Br Reaction and the Temperature Dependence of the Activation Energy of CH4 + Br -> CH3 + HBr}, journal = {The Journal of Physical Chemistry A}, volume = {127}, number = {33}, abstract = {The rate coefficient of the reaction of CH3 with HBr was measured and calculated in the temperature range 225–960 K. The results of the measurements performed in a flow apparatus with mass spectrometric detection agree very well with the quasiclassical trajectory calculations performed on a previously developed potential energy surface. The experimental rate coefficients are described well with a double-exponential fit, k1(exp) = [1.44 × 10–12 exp(219/T) + 6.18 × 10–11 exp(−3730/T)] cm3 molecule–1 s–1. The individual rate coefficients below 500 K accord with the available experimental data as does the slightly negative activation energy in this temperature range, −1.82 kJ/mol. At higher temperatures, the activation energy was found to switch sign and it rises up to about an order of magnitude larger positive value than that below 500 K, and the rate coefficient is about 50% larger at 960 K than that around room temperature. The rate coefficients calculated with the quasiclassical trajectory method display the same tendencies and are within about 8% of the experimental data between 960 and 300 K and within 25% below that temperature. The significant variation of the magnitude of the activation energy can be reconciled with the tabulated heats of formation only if the activation energy of the reverse CH4 + Br reaction also significantly increases with the temperature.}, year = {2024}, type= {article}, }
- P.K. Najeeb, M.H. Stockett, E.K. Anderson, M.K. Kristiansson, P. Reinhed, A. Simonsson, S. Rosén, R.D. Thomas, K.C. Chartkunchand, H. Gnaser, R. Golser, D. Hanstorp, Ã…. Larson, H. Cederquist, H.T. Schmidt, and H. Zettergren, “Stability and Cooling of the C72- Dianion” Phys. Rev. Lett., vol. 131, 11 (2024).[Bibtex]
@article{ author = {P.K. Najeeb, M.H. Stockett, E.K. Anderson, M.K. Kristiansson, P. Reinhed, A. Simonsson, S. Rosén, R.D. Thomas, K.C. Chartkunchand, H. Gnaser, R. Golser, D. Hanstorp, Ã…. Larson, H. Cederquist, H.T. Schmidt, and H. Zettergren}, title = {Stability and Cooling of the C72- Dianion}, journal = {Phys. Rev. Lett.}, volume = {131}, number = {11}, abstract = {We have studied the stability of the smallest long-lived all carbon molecular dianion (C2− 7) in new time domains and with a single ion at a time using a cryogenic electrostatic ion-beam storage ring. We observe spontaneous electron emission from internally excited dianions on millisecond timescales and monitor the survival of single colder C2− 7 molecules on much longer timescales. We find that their intrinsic lifetime exceeds several minutes—6 orders of magnitude longer than established from earlier experiments on C2− 7. This is consistent with our calculations of vertical electron detachment energies predicting one inherently stable isomer and one isomer which is stable or effectively stable behind a large Coulomb barrier for C2− 7→C− 7+𝑒− separation.}, year = {2024}, type= {article}, }
- A. Dochain, V. M. Andrianarijaona, and X. Urbain, “Isotope effect for the mutual neutralization reaction at low collision energies: He+ + H-” Phys. Rev. A, vol. 108, 4 (2024).[Bibtex]
@article{ author = {A. Dochain, V. M. Andrianarijaona, and X. Urbain}, title = {Isotope effect for the mutual neutralization reaction at low collision energies: He+ + H-}, journal = {Phys. Rev. A}, volume = {108}, number = {4}, abstract = {We measured the branching ratios of the He++H− and He++D− mutual neutralization at a collision energy below 25 meV. Those are correctly reproduced using the Landau-Zener model applied to potential energy curves computed by an anion-centered asymptotic model. The analyticity of both models allows getting a deeper insight into the reaction. It allows defining a low collision energy regime for the mutual neutralization at which the collision energy no longer affects the branching ratios. Using those models, we explain how heavier isotopes favor the production of higher excited states.}, year = {2024}, type= {article}, }
- Yining Huo, Mónica Cangahuala, Vicente Zamudio-Bayer, Marcelo Goulart, Markus Kubin, Martin Timm, J. Lau, Bernd Issendorff, Ronnie Hoekstra, Shirin Faraji, Thomas Schlathölter, “A comparative laboratory study of soft X-ray-induced ionization and fragmentation of five small PAH cations” The European Physical Journal D, vol. 77, (2024).[Bibtex]
@article{ author = {Yining Huo, Mónica Cangahuala, Vicente Zamudio-Bayer, Marcelo Goulart, Markus Kubin, Martin Timm, J. Lau, Bernd Issendorff, Ronnie Hoekstra, Shirin Faraji, Thomas Schlathölter}, title = {A comparative laboratory study of soft X-ray-induced ionization and fragmentation of five small PAH cations}, journal = {The European Physical Journal D}, volume = {77}, number = {}, abstract = {The interaction between polycyclic aromatic hydrocarbon (PAH) radical cations and X-rays predominantly leads to photofragmentation, a process that strongly depends on PAH size and geometry. In our experiments, five prototypical PAHs were exposed to monochromatic soft X-ray photons with energies in the C K-edge regime. As a function of soft X-ray photon energy, photoion yields were obtained by means of time-of-flight mass spectrometry. The resulting near-edge X-ray absorption mass spectra were interpreted using time-dependent density functional theory (TD-DFT) with a short-range corrected functional. We found that the carbon backbone of anthracene $$^+$$ + (C $$_{14}$$ 14 H $$_{10}^+$$ 10 + ), pyrene $$^+$$ + (C $$_{16}$$ 16 H $$_{10}^+$$ 10 + ) and coronene $$^+$$ + (C $$_{24}$$ 24 H $$_{12}^+$$ 12 + ) can survive soft X-ray absorption, even though mostly intermediate size fragments are formed. In contrast, for hexahydropyrene $$^+$$ + (C $$_{16}$$ 16 H $$_{16}^+$$ 16 + ) and triphenylene $$^+$$ + (C $$_{18}$$ 18 H $$_{12}^+$$ 12 + ) molecular survival is not observed and the fragmentation pattern is dominated by small fragments. For a given excitation energy, molecular survival evidently does not simply correlate with PAH size but strongly depends on other PAH properties. }, year = {2024}, type= {article}, }
- Giuseppe Mattioli, Robin Schürmann, Chiara Nicolafrancesco, Alexandre Giuliani, Aleksandar R. Milosavljević , “Effect of Protonation on the Molecular Structure of Adenosine 5'-Triphosphate: A Combined Theoretical and Near Edge X-ray Absorption Fine Structure Study” The Journal of Physical Chemistry Letters, vol. 14, 45 (2024).[Bibtex]
@article{ author = {Giuseppe Mattioli, Robin Schürmann, Chiara Nicolafrancesco, Alexandre Giuliani, Aleksandar R. Milosavljević }, title = {Effect of Protonation on the Molecular Structure of Adenosine 5'-Triphosphate: A Combined Theoretical and Near Edge X-ray Absorption Fine Structure Study}, journal = {The Journal of Physical Chemistry Letters}, volume = {14}, number = {45}, abstract = {The present work combines the near edge X-ray absorption mass spectrometry of a protonated adenosine 5′-triphosphate (ATP) molecule isolated in an ion trap with (time-dependent) density functional theory calculations. Our study unravels the effect of protonation on the ATP structure and its spectral properties, providing structure–property relationships at atomistic resolution for protonated ATP (ATPH) isolated in the gas-phase conditions. On the other hand, the present C and N K-edge X-ray absorption spectra of isolated ATPH appear closely like those previously reported for solvated ATP at low pH. Therefore, the present work should be relevant for further investigation and modeling of structure–function properties of protonated adenine and ATP in complex biological environments.}, year = {2024}, type= {article}, }
- Jelena Tamuliene and Teodora Kirova, “Discrimination of leucine and isoleucine via fragmentation by electromagnetic field.” Journal of molecular modeling, vol. 30, 1 (2024).[Bibtex]
@article{ author = {Jelena Tamuliene and Teodora Kirova}, title = {Discrimination of leucine and isoleucine via fragmentation by electromagnetic field.}, journal = {Journal of molecular modeling}, volume = {30}, number = {1}, abstract = {Context We conduct comparative numerical studies of the effects of electric dipole field and electromagnetic radiation field on the amino acids leucine and isoleucine. Since they are structural isomers, distinguishing them by mass is a non-trivial task, while determination of protein structure can be crucial on many occasions. We emphasize the influence of the magnetic field of radiation by utilizing a modified basis sets with correction coefficients to the and orbitals following the Anisotropic Gaussian Type Orbitals method. Studying the electric potential of the isomers in dipole electric or electromagnetic fields proves that the different layout of leucine vs isoleucine is the main reason why some fragments could not be formed during chemical bond cleavage. Comparison of the chemical structure of the fragments created due to the decomposition of the isomers in the dipole electric or electromagnetic fields shows that their decomposition products are different. These findings can be used also for discrimination between the two isoleucine conformers, for which the cleavage starts at different values of the dipole electric field strength, as well as the products of the decomposition reaction are not identical. Our numerical calculations of the fragmentation outcomes, taking into account the magnetic field effects, can serve as a guidance for discrimination between the isomers/conformers. Methods We applied the Becke’s three-parameter hybrid functional approach with non-local correlation by Lee, Yang, and Parr ( ), together with the basis set as it is implemented in the GAUSSIAN09 quantum chemistry package in order to obtain the most stable conformers of leucine and isoleucine. We used the options provided by GAUSSIAN09 to add finite external field in order to perform the calculations of leucine and isoleucine in the electric dipole and electromagnetic fields. The Anisotropic Gaussian Type Orbitals method was used to obtain the correction coefficients which modify the original basis set in order to account for the effects of magnetic field of radiation. Results were visualized and the electrical potentials analyzed by the Molden visualization program.}, year = {2024}, type= {article}, }
- János Zsolt Mezei, Mehdi A. Ayouz, Andrea Orbán, Abdillah Abdoulanziz, Dahbia Talbi, David O. Kashinski, Emeric Bron, Viatcheslav Kokoouline & Ioan F. Schneider , “Dissociative recombination of N2H+: a revisited study” The European Physical Journal Special Topics, vol. 232, (2024).[Bibtex]
@article{ author = {János Zsolt Mezei, Mehdi A. Ayouz, Andrea Orbán, Abdillah Abdoulanziz, Dahbia Talbi, David O. Kashinski, Emeric Bron, Viatcheslav Kokoouline & Ioan F. Schneider }, title = {Dissociative recombination of N2H+: a revisited study}, journal = {The European Physical Journal Special Topics}, volume = {232}, number = {}, abstract = {Dissociative recombination of N2H+ is explored in a two-step theoretical study. In a first step, a diatomic (1D) rough model with a frozen NN bond and frozen angles is adopted, in the framework of the multichannel quantum defect theory (MQDT). The importance of the indirect mechanism and of the bending mode is revealed, in spite of the disagreement between our cross section and the experimental one. In the second step, we use our recently elaborated 3D approach based on the normal mode approximation combined with R-matrix theory and MQDT. This approach results in satisfactory agreement with storage-ring measurements, significantly better at very low energy than the former calculations.}, year = {2024}, type= {article}, }
- DarÃo Barreiro-Lage, Jacopo Chiarinelli, Paola Bolognesi, Robert Richter, Henning Zettergren, Mark H. Stockett, Sergio DÃaz-Tendero and Lorenzo Avaldi , “Photofragmentation specificity of photoionized cyclic amino acids (diketopiperazines) as precursors of peptide building blocks” Phys. Chem. Chem. Phys., vol. 25, 23 (2024).[Bibtex]
@article{ author = {DarÃo Barreiro-Lage, Jacopo Chiarinelli, Paola Bolognesi, Robert Richter, Henning Zettergren, Mark H. Stockett, Sergio DÃaz-Tendero and Lorenzo Avaldi }, title = {Photofragmentation specificity of photoionized cyclic amino acids (diketopiperazines) as precursors of peptide building blocks}, journal = {Phys. Chem. Chem. Phys.}, volume = {25}, number = {23}, abstract = {The photoionisation and photofragmentation of the two cyclic dipetides cyclo(alanyl-glycine) cGA and cyclo(glycyl-glycine) cGG{,} have been studied combining experiments and simulations. State selected fragments from the ionized molecules are detected using photo-electron photo-ion coincidence (PEPICO) measurements and specific fragmentation paths are identified and characterized via the use of ion-neutral coincidence maps. The simulations{,} performed using Quantum Chemistry methods{,} allow us to infer the fragmentation mechanisms of the ionized and excited molecules. We show that ring opening is followed by emission of the neutral fragments CO and HNCO. In the case of cGG the emission of neutral CO leads to a metastable structure that breaks producing small cationic fragments. The studied cyclic dipeptides evolve under ionizing radiation generating different small aziridin moieties and oxazolidinones. These two species are key reactants to elongate producing peptide chains. The corresponding mechanisms have been computed and show that the reaction requires very low energy and may occur in the presence of ionizing radiation.}, year = {2024}, type= {article}, }
- Lukas Tiefenthaler, Paul Scheier, Ewa Erdmann, Néstor F. Aguirre, Sergio DÃaz-Tendero, Thomas F. M. Luxford and Jaroslav KociÅ¡ek , “Non-ergodic fragmentation upon collision-induced activation of cysteine-water cluster cations” Phys. Chem. Chem. Phys., vol. 25, 7 (2024).[Bibtex]
@article{ author = {Lukas Tiefenthaler, Paul Scheier, Ewa Erdmann, Néstor F. Aguirre, Sergio DÃaz-Tendero, Thomas F. M. Luxford and Jaroslav KociÅ¡ek }, title = {Non-ergodic fragmentation upon collision-induced activation of cysteine-water cluster cations}, journal = {Phys. Chem. Chem. Phys.}, volume = {25}, number = {7}, abstract = {Cysteine–water cluster cations Cys(H2O)3{,}6+ and Cys(H2O)3{,}6H+ are assembled in He droplets and probed by tandem mass spectrometry with collision-induced activation. Benchmark experimental data for this biologically important system are complemented with theory to elucidate the details of the collision-induced activation process. Experimental energy thresholds for successive release of water are compared to water dissociation energies from DFT calculations showing that clusters do not only fragment exclusively by sequential emission of single water molecules but also by the release of small water clusters. Release of clustered water is observed also in the ADMP (atom centered density matrix propagation) molecular dynamics model of small Cys(H2O)3+ and Cys(H2O)3H+ clusters. For large clusters Cys(H2O)6+ and Cys(H2O)6H+ the less computationally demanding statistical Microcanonical Metropolis Monte–Carlo method (M3C) is used to model the experimental fragmentation patterns. We are able to detail the energy redistribution in clusters upon collision activation. In the present case{,} about two thirds of the collision energy redistribute via an ergodic process{,} while the remaining one third is transferred into a non-ergodic channel leading to ejection of a single water molecule from the cluster. In contrast to molecular fragmentation{,} which can be well described by statistical models{,} modelling of collision-induced activation of weakly bound clusters requires inclusion of non-ergodic processes.}, year = {2024}, type= {article}, }
- P.A.S. Randi, S. Kumar, A.I. Lozano, M.H.F. Bettega, S.V. Hoffmann, N.C. Jones, A. Souza Barbosa, P. Limão-Vieira , “Valence and Rydberg excitations of 2-fluorotoluene in the 4.4-10.8 eV photoabsorption energy region” Journal of Quantitative Spectroscopy and Radiative Transfer, vol. 303, (2024).[Bibtex]
@article{ author = {P.A.S. Randi, S. Kumar, A.I. Lozano, M.H.F. Bettega, S.V. Hoffmann, N.C. Jones, A. Souza Barbosa, P. Limão-Vieira }, title = {Valence and Rydberg excitations of 2-fluorotoluene in the 4.4-10.8 eV photoabsorption energy region}, journal = {Journal of Quantitative Spectroscopy and Radiative Transfer}, volume = {303}, number = {}, abstract = {The electronic state spectroscopy of 2-fluorotoluene in the gas phase has been investigated for the first time using high-resolution vacuum ultraviolet photoabsorption experiments in the 4.4–10.8 eV energy-range, with absolute cross-section measurements obtained. Additionally, we also present a novel set of ab initio calculations (vertical excitation energies and oscillator strengths) at two different levels of theory, equation-of-motion coupled-cluster singles and doubles (EOM-CCSD) and time-dependent density functional theory (TD-DFT). These are used in the assignment of valence, mix valence-Rydberg and Rydberg transitions, with the associated vibronic series analysed. The measured absolute photoabsorption cross-sections have been used to calculate the photolysis lifetime of 2-fluorotoluene in the Earth's atmosphere.}, year = {2024}, type= {article}, }
- Edwin Kukk, Lassi Pihlava, Kuno Kooser, Christian StrÃ¥hlman, Sylvain Maclot and Antti Kivimäki, “Energy-dependent timescales in the dissociation of diiodothiophene dication” Phys. Chem. Chem. Phys., vol. 25, 7 (2024).[Bibtex]
@article{ author = {Edwin Kukk, Lassi Pihlava, Kuno Kooser, Christian StrÃ¥hlman, Sylvain Maclot and Antti Kivimäki}, title = {Energy-dependent timescales in the dissociation of diiodothiophene dication}, journal = {Phys. Chem. Chem. Phys.}, volume = {25}, number = {7}, abstract = {Photodissociation molecular dynamics of gas-phase 2{,}5-diiodothiophene molecules was studied in an electron-energy-resolved electron-multi-ion coincidence experiment performed at the FinEstBeAMS beamline of MAX IV synchrotron. Following the photoionization of the iodine 4d subshell and the Auger decay{,} the dissociation landscape of the molecular dication was investigated as a function of the Auger electron energy. Concentrating on an major dissociation pathway{,} C4H2I2S2+ → C4H2S+ + I+ + I{,} and accessing the timescales of the process via ion momentum correlation analysis{,} it was revealed how this three-body process changes depending on the available internal energy. Using a generalized secondary dissociation model{,} the process was shown to evolve from secondary dissociation regime towards concerted dissociation as the available energy increased{,} with the secondary dissociation time constant changing from 1.5 ps to 129 fs. The experimental results were compared with simulations using a stochastic charge-hopping molecular mechanics model. It represented the observed trend and also gave a fair quantitative agreement with the experiment.}, year = {2024}, type= {article}, }
- Jack E. Fulker, Alejandro Gutiérrez-Quintanilla, Wendy A. Brown, Gustavo A. Pino, Antoine Hacquard, Ana Niedojadlo, Jennifer A. Noble, “Gas phase electronic spectra of xylene-water aggregates” Journal of Molecular Spectroscopy, vol. 393, (2024).[Bibtex]
@article{ author = {Jack E. Fulker, Alejandro Gutiérrez-Quintanilla, Wendy A. Brown, Gustavo A. Pino, Antoine Hacquard, Ana Niedojadlo, Jennifer A. Noble}, title = {Gas phase electronic spectra of xylene-water aggregates}, journal = {Journal of Molecular Spectroscopy}, volume = {393}, number = {}, abstract = {Using a jet spectroscopy molecular beam setup, gas phase electronic spectra of three xylene isomers (para, meta and ortho) have been collected for the neutral monomer species as well as for their clusters with one and two water molecules. Scans at a resolution of ±0.02 nm showed a clear 0–0 transition for each xylene isomer as well as the vibronic progression. The spectra were assigned with the help of Franck–Condon factor PGOPHER simulations from theoretical studies at the CAM-B3LYP/aug-cc-pVDZ level of theory. The vibronic spectra of the xylene⋅H2O and xylene⋅(H2O)2 clusters showed broad features between 36800–38400 cm−1 (260–272 nm) for p- and m-xylene, while the water clusters of o-xylene gave more defined bands. The separation of the vibronic bands in the clusters mirrors the progression of the neutral monomers implying that, for the S1 ← S0 transition, it is the same vibrational modes that are involved in the monomer as in the clusters with water. Both the separation and the spectral width of the bands can be explained by the calculated differences in geometries of the clusters in the ground and first electronic excited states.}, year = {2024}, type= {article}, }
- Jason W. L. Lee, Mark H. Stockett, Eleanor K. Ashworth,José E. Navarro Navarrete, Eva Gougoula, Diksha Garg, MingChao Ji, Boxing Zhu, Suvasthika Indrajith, Henning Zettergren, Henning T. Schmidt, James N. Bull, “Cooling dynamics of energized naphthalene and azulene radical cations” The Journal of Chemical Physics, vol. 158, 17 (2024).[Bibtex]
@article{ author = {Jason W. L. Lee, Mark H. Stockett, Eleanor K. Ashworth,José E. Navarro Navarrete, Eva Gougoula, Diksha Garg, MingChao Ji, Boxing Zhu, Suvasthika Indrajith, Henning Zettergren, Henning T. Schmidt, James N. Bull}, title = {Cooling dynamics of energized naphthalene and azulene radical cations}, journal = {The Journal of Chemical Physics}, volume = {158}, number = {17}, abstract = {Naphthalene and azulene are isomeric polycyclic aromatic hydrocarbons (PAHs) and are topical in the context of astrochemistry due to the recent discovery of substituted naphthalenes in the Taurus Molecular Cloud-1 (TMC-1). Here, the thermal- and photo-induced isomerization, dissociation, and radiative cooling dynamics of energized (vibrationally hot) naphthalene (Np+) and azulene (Az+) radical cations, occurring over the microsecond to seconds timescale, are investigated using a cryogenic electrostatic ion storage ring, affording “molecular cloud in a box” conditions. Measurement of the cooling dynamics and kinetic energy release distributions for neutrals formed through dissociation, until several seconds after hot ion formation, are consistent with the establishment of a rapid (sub-microsecond) Np+ ⇌ Az+ quasi-equilibrium. Consequently, dissociation by C2H2-elimination proceeds predominantly through common Az+ decomposition pathways. Simulation of the isomerization, dissociation, recurrent fluorescence, and infrared cooling dynamics using a coupled master equation combined with high-level potential energy surface calculations [CCSD(T)/cc-pVTZ], reproduce the trends in the measurements. The data show that radiative cooling via recurrent fluorescence, predominately through the Np+ D0 ← D2 transition, efficiently quenches dissociation for vibrational energies up to ≈1 eV above dissociation thresholds. Our measurements support the suggestion that small cations, such as naphthalene, may be more abundant in space than previously thought. The strategy presented in this work could be extended to fingerprint the cooling dynamics of other PAH ions for which isomerization is predicted to precede dissociation.}, year = {2024}, type= {article}, }
- Jozo.J. Jureta, Bratislav P. Marinković, Lorenzo Avaldi, “The N4,5 - OO Auger and "N3" N4,5O2,3 Coster-Kronig spectra of xenon induced by electron impact” Advances in Space Research, vol. 71, 2 (2024).[Bibtex]
@article{ author = {Jozo.J. Jureta, Bratislav P. Marinković, Lorenzo Avaldi}, title = {The N4,5 - OO Auger and "N3" N4,5O2,3 Coster-Kronig spectra of xenon induced by electron impact}, journal = {Advances in Space Research}, volume = {71}, number = {2}, abstract = {The N4,5OO Auger electron spectrum in the kinetic energy region (14–37) eV has been measured with high resolution at electron incident energies between 71 eV and 2019 eV. The Auger and satellite lines are assigned by comparison with previous literature data. Several states which correspond to the resonant Auger transitions from the 4d3/2, 5/2 6p states are observed. The PCI effects on the N5-O2,3O2,3(1S0) Auger peak when the incident electron energy approaches to the N5 edge (67.55 eV) is investigated and it is found that the dependence of the energy shift on the excess energy, Eexc, is well represented by the function Eexcβ with β = (-1.40 ± 0.05). The “N3” N4,5O2,3 Coster-Kronig spectrum is measured at various electron incident energies. The assignments of the features are made in comparison with a similar spectrum from synchrotron radiation measured by Kivimäki et al. [J. Electron Spectrosc. Relat. Phenom. 1999, 101–103, 43–47]. The Auger spectrum in the kinetic energy regions (68–78) eV and (90–138) eV is observed for the first time in an electron impact experiment and a comparison is made with the photoionization experiment by Hikosaka et al. [Phys. Rev. A 2007, 76, 032708].}, year = {2024}, type= {article}, }
- Giuseppe Mattioli, Lorenzo Avaldi, Paola Bolognesi, Annarita Casavola, Filippo Morini, Thomas Van Caekenberghe, John D. Bozek, Mattea C. Castrovilli, Jacopo Chiarinelli, Alicja Domaracka, Suvasthika Indrajith, Sylvain Maclot; Aleksandar R. Milosavljević, Chiara Nicolafrancesco, Christophe Nicolas, Patrick Rousseau , “A study of the valence photoelectron spectrum of uracil and mixed water-uracil clusters” The Journal of Chemical Physics, vol. 158, 11 (2024).[Bibtex]
@article{ author = {Giuseppe Mattioli, Lorenzo Avaldi, Paola Bolognesi, Annarita Casavola, Filippo Morini, Thomas Van Caekenberghe, John D. Bozek, Mattea C. Castrovilli, Jacopo Chiarinelli, Alicja Domaracka, Suvasthika Indrajith, Sylvain Maclot; Aleksandar R. Milosavljević, Chiara Nicolafrancesco, Christophe Nicolas, Patrick Rousseau }, title = {A study of the valence photoelectron spectrum of uracil and mixed water-uracil clusters}, journal = {The Journal of Chemical Physics}, volume = {158}, number = {11}, abstract = {The valence ionization of uracil and mixed water–uracil clusters has been studied experimentally and by ab initio calculations. In both measurements, the spectrum onset shows a red shift with respect to the uracil molecule, with the mixed cluster characterized by peculiar features unexplained by the sum of independent contributions of the water or uracil aggregation. To interpret and assign all the contributions, we performed a series of multi-level calculations, starting from an exploration of several cluster structures using automated conformer-search algorithms based on a tight-binding approach. Ionization energies have been assessed on smaller clusters via a comparison between accurate wavefunction-based approaches and cost-effective DFT-based simulations, the latter of which were applied to clusters up to 12 uracil and 36 water molecules. The results confirm that (i) the bottom-up approach based on a multilevel method [Mattioli et al. Phys. Chem. Chem. Phys. 23, 1859 (2021)] to the structure of neutral clusters of unknown experimental composition converges to precise structure–property relationships and (ii) the coexistence of pure and mixed clusters in the water–uracil samples. A natural bond orbital (NBO) analysis performed on a subset of clusters highlighted the special role of H-bonds in the formation of the aggregates. The NBO analysis yields second-order perturbative energy between the H-bond donor and acceptor orbitals correlated with the calculated ionization energies. This sheds light on the role of the oxygen lone-pairs of the uracil CO group in the formation of strong H-bonds, with a stronger directionality in mixed clusters, giving a quantitative explanation for the formation of core–shell structures.}, year = {2024}, type= {article}, }
- Jérôme Bernard, MingChao Ji, Suvasthika Indrajith, Mark H. Stockett, José E. Navarro Navarrete, Naoko Kono, Henrik Cederquist, Serge Martin, Henning T. Schmidt and Henning Zettergren , “Efficient radiative cooling of tetracene cations C18H12+: absolute recurrent fluorescence rates as a function of internal energy ” Phys. Chem. Chem. Phys., vol. 25, 15 (2024).[Bibtex]
@article{ author = {Jérôme Bernard, MingChao Ji, Suvasthika Indrajith, Mark H. Stockett, José E. Navarro Navarrete, Naoko Kono, Henrik Cederquist, Serge Martin, Henning T. Schmidt and Henning Zettergren }, title = {Efficient radiative cooling of tetracene cations C18H12+: absolute recurrent fluorescence rates as a function of internal energy }, journal = {Phys. Chem. Chem. Phys.}, volume = {25}, number = {15}, abstract = {We have measured recurrent fluorescence (RF) cooling rates of internally hot tetracene cations{,} C18H12+{,} as functions of their storage times and internal energies in two different electrostatic ion-beam storage rings – the cryogenic ring DESIREE with a circumference of 8.6 meters in Stockholm and the much smaller room temperature ring Mini-Ring in Lyon{,} which has a circumference of 0.71 meters. The RF rates were measured to be as high as 150 to 1000 s−1 for internal energies in the 7 to 9.4 eV energy range{,} where we have probed the time evolution of the internal energy distribution with nanosecond laser pulses with a 1 kHz repetition rate. These RF rates are found to be significantly higher than those of previously investigated smaller PAHs such as e.g. anthracene and naphthalene{,} for which the lowest non-forbidden electronic excited state{,} the D2 state{,} is populated with a smaller probability by inverse internal conversion. Furthermore{,} the D2–D0 transition rate is smaller for these smaller molecules than for tetracene. The complementary features of the two storage rings allow for RF rate measurements in a broader internal energy range than has been possible before. The smaller sampling period of about 6 μs in Mini-Ring is ideal to study the cooling dynamics of the hotter ions that decay fast{,} whereas DESIREE with a sampling period of about 60 μs is better suited to study the colder ions that decay on longer timescales ranging up to hundreds of milliseconds. The excellent agreement between the two series of measurements in the region where they overlap demonstrates the complementarity of the two electrostatic ion-beam storage rings.}, year = {2024}, type= {article}, }
- Luiz V. S. Dalagnol, Márcio H. F. Bettega, Nykola C. Jones, Søren V. Hoffmann, Alessandra Souza Barbosa, and Paulo Limão-Vieira, “Electronic State Spectroscopy of Nitromethane and Nitroethane” The Journal of Physical Chemistry A, vol. 127, 6 (2024).[Bibtex]
@article{ author = {Luiz V. S. Dalagnol, Márcio H. F. Bettega, Nykola C. Jones, Søren V. Hoffmann, Alessandra Souza Barbosa, and Paulo Limão-Vieira}, title = {Electronic State Spectroscopy of Nitromethane and Nitroethane}, journal = {The Journal of Physical Chemistry A}, volume = {127}, number = {6}, abstract = {High-resolution photoabsorption cross-sections in the 3.7–10.8 eV energy range are reinvestigated for nitromethane (CH3NO2), while for nitroethane (C2H5NO2), they are reported for the first time. New absorption features are observed for both molecules which have been assigned to vibronic excitations of valence, Rydberg, and mixed valence-Rydberg characters. In comparison with nitromethane, nitroethane shows mainly broad absorption bands with diffuse structures, which can be interpreted as a result of the side-chain effect contributing to an increased number of internal degrees of freedom. New theoretical quantum chemical calculations performed at the time-dependent density functional theory (TD-DFT) level were used to qualitatively help interpret the recorded photoabsorption spectra. From the photoabsorption cross-sections, photolysis lifetimes in the terrestrial atmosphere have been obtained for both compounds. Relevant internal conversion from Rydberg to valence character is noted for both molecules, while the nuclear dynamics of CH3NO2 and C2H5NO2 along the C–N reaction coordinate have been evaluated through potential energy curves at the TD-DFT level of theory, showing that the pre-dissociative character is more prevalent in nitromethane than in nitroethane.}, year = {2024}, type= {article}, }
- Jelena B. Maljković, Jelena Vukalović, Zoran D. PeÅ¡ić, Francisco Blanco, Gustavo GarcÃa & Bratislav P. Marinković , “Experimental and theoretical study on elastic electron interaction with halothane molecule in the intermediate energy range” The European Physical Journal Plus, vol. 138, (2024).[Bibtex]
@article{ author = {Jelena B. Maljković, Jelena Vukalović, Zoran D. PeÅ¡ić, Francisco Blanco, Gustavo GarcÃa & Bratislav P. Marinković }, title = {Experimental and theoretical study on elastic electron interaction with halothane molecule in the intermediate energy range}, journal = {The European Physical Journal Plus}, volume = {138}, number = {}, abstract = {We present a combined theoretical and experimental absolute differential (DCS) and integral (ICS) cross sections for elastic electron scattering from halothane molecule in the intermediate energy range from 50 to 300 eV, which is motivated by its evident impact on global warming and ozone depletion. Experiments were carried out in the angular range from 20 to 110 degrees using a crossed-beam-based equipment. Using argon as the reference gas, relative DCSs were normalized on an absolute scale using the relative flow technique. These DCSs were then extrapolated and integrated to generate experimental ICS. With the use of an independent atom model and the screening corrected additivity rule with interference effects incorporated (IAM-SCAR+I), the theoretical differential and integral cross sections were calculated. In the whole energy and angular range, calculated cross sections agree well with experimental measurements}, year = {2024}, type= {article}, }
- Mark H. Stockett, James N. Bull, Henrik Cederquist, Suvasthika Indrajith, MingChao Ji, José E. Navarro Navarrete, Henning T. Schmidt, Henning Zettergren & Boxing Zhu , “Efficient stabilization of cyanonaphthalene by fast radiative cooling and implications for the resilience of small PAHs in interstellar clouds” Nature Communications, vol. 14, (2024).[Bibtex]
@article{ author = {Mark H. Stockett, James N. Bull, Henrik Cederquist, Suvasthika Indrajith, MingChao Ji, Jos̩ E. Navarro Navarrete, Henning T. Schmidt, Henning Zettergren & Boxing Zhu }, title = {Efficient stabilization of cyanonaphthalene by fast radiative cooling and implications for the resilience of small PAHs in interstellar clouds}, journal = {Nature Communications}, volume = {14}, number = {}, abstract = {After decades of searching, astronomers have recently identified specific Polycyclic Aromatic Hydrocarbons (PAHs) in space. Remarkably, the observed abundance of cyanonaphthalene (CNN, C10H7CN) in the Taurus Molecular Cloud (TMC-1) is six orders of magnitude higher than expected from astrophysical modeling. Here, we report unimolecular dissociation and radiative cooling rate coefficients of the 1-CNN isomer in its cationic form. These results are based on measurements of the time-dependent neutral product emission rate and kinetic energy release distributions produced from an ensemble of internally excited 1-CNN+ studied in an environment similar to that in interstellar clouds. We find that Recurrent Fluorescence Рradiative relaxation via thermally populated electronic excited states Рefficiently stabilizes 1-CNN+, owing to a large enhancement of the electronic transition probability by vibronic coupling. Our results help explain the anomalous abundance of CNN in TMC-1 and challenge the widely accepted picture of rapid destruction of small PAHs in space. The abundances of small Polycyclic Aromatic Hydrocarbons (PAHs) observed in interstellar clouds has surprised astronomers and confounded astrochemical models. Here, the authors show that fast radiative cooling by Recurrent Fluorescence efficiently stabilizes the small PAH cation 1-cyanonaphthalene.}, year = {2024}, type= {article}, }
- Dr. Orlando Carrillo-Bohórquez, Dr. Ã…lvaro Valdés, Dr. Rita Prosmiti, “Computational Energy Spectra of the H2O@C70 Endofullerene” ChemPhysChem, vol. 24, 23 (2024).[Bibtex]
@article{ author = {Dr. Orlando Carrillo-Bohórquez, Dr. Ålvaro Valdés, Dr. Rita Prosmiti}, title = {Computational Energy Spectra of the H2O@C70 Endofullerene}, journal = {ChemPhysChem}, volume = {24}, number = {23}, abstract = {Abstract A water molecule confined inside the C70 fullerene was quantum-mechanically described using a computational approach within the MCTDH framework. Such procedure involves the development of a full-dimensional coupled hamiltonian, with an exact kinetic energy operator, including all rotational, translational and vibrational degrees of freedom of the endofullerene system. In turn, through an effective pairwise potential model, the ground and rotationally excited states of the encapsulated H2O inside the C70 cage were calculated, and traced back to the isotropic case of the H2O@C60 endofullerene in order to understand the nature and physical origin of the symmetry breaking observed experimentally in the latter system. Moreover, the computational scheme used here allows to study the quantization of the translational movement of the encapsulated water molecule inside the C70 fullerene, and to investigate the confinement effects in the vibrational energy levels of the H2O@C70 system.}, year = {2024}, type= {article}, }
- J.M. Gong, K. TÅ‘kési, X. Liu, B. Da, H. Yoshikawa, S. Tanuma, Z.J. Ding , “Determination of electron inelastic mean free path and stopping power of hafnium dioxide” Results in Physics, vol. 51, (2024).[Bibtex]
@article{ author = {J.M. Gong, K. TÅ‘kési, X. Liu, B. Da, H. Yoshikawa, S. Tanuma, Z.J. Ding }, title = {Determination of electron inelastic mean free path and stopping power of hafnium dioxide}, journal = {Results in Physics}, volume = {51}, number = {}, abstract = {We present inelastic mean free path (IMFP) and stopping power data of the hafnium dioxide applying the relativistic dielectric response theory. The energy loss function (ELF) derived from reflection electron energy loss spectroscopy spectrum with the reverse Monte Carlo method was used for the first time to obtain the IMFP and stopping power of HfO2. The probability of the energy loss is determined by the dielectric response function εq,ω as a function of the frequency ω and the wavenumber q of the electromagnetic disturbance. Two algorithms, namely the full Penn algorithm (FPA) and the super-extended Mermin algorithm (SMA), were employed to expand the optical energy loss function, Im-1/ε0,ω, into the q,ω-plane. The results indicate that the IMFP and the stopping power obtained by using both algorithms are consistent at high electron energies, but show differences at low electron energies (less than ∼ 70 eV). This discrepancy arises from the consideration of the finite plasmon lifetimes effect in the SMA model, while it is neglected in the FPA model. Additionally, we observed that the band gap has a significant influence on the IMFP and the stopping power at low electron energies. Typically, the inclusion of the band gap leads to an increase in the IMFP, because transition channels with energies larger than E-Eg-Ev are prohibited.}, year = {2024}, type= {article}, }
- R. Rodriguez-Segundo, D.J. Arismendi-Arrieta, R. Prosmiti, “A Benchmark Protocol for DFT Approaches and Data-Driven Models for Halide-Water Clusters” Molecules, vol. 27, 5 (2022).[Bibtex]
@article{ author = {R. Rodriguez-Segundo, D.J. Arismendi-Arrieta, R. Prosmiti}, title = {A Benchmark Protocol for DFT Approaches and Data-Driven Models for Halide-Water Clusters}, journal = {Molecules}, volume = {27}, number = {5}, abstract = {}, year = {2022}, type= {paper 1}, }
- B. Milovanovic, J. Novak, M. Etinski, W. Domcke, N. Doslic, “On the propensity of formation of cyclobutane dimers in face-to-face and face-to-back uracil stacks in solution” Physical Chemistry Chemical Physics, vol. 24, 14836 (2022).[Bibtex]
@article{ author = {B. Milovanovic, J. Novak, M. Etinski, W. Domcke, N. Doslic}, title = {On the propensity of formation of cyclobutane dimers in face-to-face and face-to-back uracil stacks in solution}, journal = {Physical Chemistry Chemical Physics}, volume = {24}, number = {14836}, abstract = {}, year = {2022}, type= {paper 1}, }
- Eleanor K. Ashworth, Mark H. Stockett, Christina Kjær, Philip C. Bulman Page, Stephen R. Meech, Steen Brøndsted Nielsen, and James N. Bull, “Complexation of Green and Red Kaede Fluorescent Protein Chromophores by a Zwitterion to Probe Electrostatic and Induction Field Effects” The Journal of Physical Chemistry A , vol. 126(7), 1158 (2022).[Bibtex]
@article{ author = {Eleanor K. Ashworth, Mark H. Stockett, Christina Kjær, Philip C. Bulman Page, Stephen R. Meech, Steen Brøndsted Nielsen, and James N. Bull}, title = {Complexation of Green and Red Kaede Fluorescent Protein Chromophores by a Zwitterion to Probe Electrostatic and Induction Field Effects}, journal = {The Journal of Physical Chemistry A }, volume = {126(7)}, number = {1158}, abstract = {}, year = {2022}, type= {paper 1}, }
- Gustav Eklund, Moa K. Kristiansson, K. C. Chartkunchand, Emma K. Anderson, Malcolm Simpson, Roland Wester, Henning T. Schmidt, Henning Zettergren, Henrik Cederquist, and Wolf D. Geppert, “Experimental lifetime of the a1Δ electronically excited state of CH −” Phys. Rev. Research , vol. 4, L012016 (2022).[Bibtex]
@article{ author = {Gustav Eklund, Moa K. Kristiansson, K. C. Chartkunchand, Emma K. Anderson, Malcolm Simpson, Roland Wester, Henning T. Schmidt, Henning Zettergren, Henrik Cederquist, and Wolf D. Geppert}, title = {Experimental lifetime of the a1Δ electronically excited state of CH −}, journal = {Phys. Rev. Research }, volume = {4}, number = { L012016}, abstract = {}, year = {2022}, type= {article}, }
- Mathias Poline, Xiang Yuan, Sylvain Badin, MingChao Ji, Stefan Rosén, Suvasthika Indrajith, Richard D. Thomas, Henning T. Schmidt, Henning Zettergren, Andre Severo Pereira Gomes, and Nicolas Sisourat, “Final-state-resolved mutual neutralization in I+ - I-” Phys. Rev. A, vol. 106, 012812 (2022).[Bibtex]
@article{ author = {Mathias Poline, Xiang Yuan, Sylvain Badin, MingChao Ji, Stefan Rosén, Suvasthika Indrajith, Richard D. Thomas, Henning T. Schmidt, Henning Zettergren, Andre Severo Pereira Gomes, and Nicolas Sisourat}, title = {Final-state-resolved mutual neutralization in I+ - I-}, journal = {Phys. Rev. A}, volume = {106}, number = {012812 }, abstract = {}, year = {2022}, type= {paper 1}, }
- Tomislav Rožić, Majdi Hochlaf, Ridha Ben Said, and NaÄ‘a DoÅ¡lić, “A Computational Approach to Nontraditional Intrinsic Luminescence: Vibrationally Resolved Absorption and Fluorescence Spectra of DABCO” The Journal of Physical Chemistry A, vol. 126(7), 1094 (2022).[Bibtex]
@article{ author = {Tomislav Rožić, Majdi Hochlaf, Ridha Ben Said, and Nađa Došlić}, title = {A Computational Approach to Nontraditional Intrinsic Luminescence: Vibrationally Resolved Absorption and Fluorescence Spectra of DABCO}, journal = {The Journal of Physical Chemistry A}, volume = {126(7)}, number = {1094}, abstract = {}, year = {2022}, type= {paper 1}, }
- Jacopo Chiarinelli, DarÃo Barreiro-Lage, Paola Bolognesi, Robert Richter, Henning Zettergren, Mark H. Stockett, Sergio DÃaz-Tendero, and Lorenzo Avaldi, “Electron and ion spectroscopy of the cyclo-alanine–alanine dipeptide” Physical Chemistry Chemical Physics, vol. 24, 5855 (2022).[Bibtex]
@article{ author = {Jacopo Chiarinelli, DarÃo Barreiro-Lage, Paola Bolognesi, Robert Richter, Henning Zettergren, Mark H. Stockett, Sergio DÃaz-Tendero, and Lorenzo Avaldi}, title = {Electron and ion spectroscopy of the cyclo-alanine–alanine dipeptide}, journal = {Physical Chemistry Chemical Physics}, volume = {24}, number = {5855}, abstract = {}, year = {2022}, type= {paper 1}, }
- Kumar, S; Kilich, T; Labuda, M; Garcia, G; Limao-Vieira, P, “Anionic states of C6Cl6 probed in electron transfer experiments” Physical Chemistry Chemical Physics, vol. 24, 1 (2022).[Bibtex]
@article{ author = {Kumar, S; Kilich, T; Labuda, M; Garcia, G; Limao-Vieira, P}, title = {Anionic states of C6Cl6 probed in electron transfer experiments}, journal = {Physical Chemistry Chemical Physics}, volume = {24}, number = {1}, abstract = {}, year = {2022}, type= {paper1}, }
- Barreiro-Lage, D; Nicolafrancesco, C; Kocisek, J; Luna, A; Kopyra, J; Alcami, M; Huber, BA; Martin, F; Domaracka, A; Rousseau, P; Diaz-Tendero, S, “Controlling the diversity of ion-induced fragmentation pathways by N-methylation of amino acids” Physical Chemistry Chemical Physics, vol. 24, 2 (2022).[Bibtex]
@article{ author = {Barreiro-Lage, D; Nicolafrancesco, C; Kocisek, J; Luna, A; Kopyra, J; Alcami, M; Huber, BA; Martin, F; Domaracka, A; Rousseau, P; Diaz-Tendero, S}, title = {Controlling the diversity of ion-induced fragmentation pathways by N-methylation of amino acids}, journal = {Physical Chemistry Chemical Physics}, volume = {24}, number = {2}, abstract = {}, year = {2022}, type= {paper1}, }
- Felix Iacob, Thomas Meltzer, János Zsolt Mezei, Ioan F Schneider, Jonathan Tennyson, “Study of bound and resonant states of NS molecule in the R-matrix approach” Journal of Physics B: Atomic, Molecular and Optical Physics, vol. 55, 23 (2024).[Bibtex]
@article{ author = {Felix Iacob, Thomas Meltzer, János Zsolt Mezei, Ioan F Schneider, Jonathan Tennyson}, title = {Study of bound and resonant states of NS molecule in the R-matrix approach}, journal = {Journal of Physics B: Atomic, Molecular and Optical Physics}, volume = {55}, number = {23}, abstract = {The bound and resonance states along with corresponding autoionization widths for nitrogen sulphide (NS) molecule are determined using electron NS+ cation scattering calculations. The calculations are performed for 2Σ+, 2Π and 2Δ total symmetries using the ab initio R-matrix method for both bound and continuum states. Calculations are performed on a grid of 106 points for internuclear separations between 1.32 and 3 Å. The resonance states yield dissociative potential curves which, when considered together with their widths, provide input for models of different electron-cation collision processes including dissociative recombination (DR), and rotational and vibrational excitation. Curves and couplings which will lead directly to DR are identified.}, year = {2024}, type= {article}, }
- Jelena Vukalović, Jelena B. Maljković, Francisco Blanco, Gustavo GarcÃa, Branko Predojević, Bratislav P. Marinković , “Absolute Differential Cross-Sections for Elastic Electron Scattering from Sevoflurane Molecule in the Energy Range from 50-300 eV” International Journal of Molecular Sciences, vol. 23, 1 (2024).[Bibtex]
@article{ author = {Jelena Vukalović, Jelena B. Maljković, Francisco Blanco, Gustavo GarcÃa, Branko Predojević, Bratislav P. Marinković }, title = {Absolute Differential Cross-Sections for Elastic Electron Scattering from Sevoflurane Molecule in the Energy Range from 50-300 eV}, journal = {International Journal of Molecular Sciences}, volume = {23}, number = {1}, abstract = {We report the results of the measurements and calculations of the absolute differential elastic electron scattering cross-sections (DCSs) from sevoflurane molecule (C4H3F7O). The experimental absolute DCSs for elastic electron scattering were obtained for the incident electron energies from 50 eV to 300 eV, and for scattering angles from 25° to 125° using a crossed electron/target beams setup and the relative flow technique for calibration to the absolute scale. For the calculations, we have used the IAM-SCAR+I method (independent atom model (IAM) applying the screened additivity rule (SCAR) with interference terms included (I)). The molecular cross-sections were obtained from the atomic data by using the SCAR procedure, incorporating interference term corrections, by summing all the relevant atomic amplitudes, including the phase coefficients. In this approach, we obtain the molecular differential scattering cross-section (DCS), which, integrated over the scattered electron angular range, gives the integral scattering cross-section (ICS). Calculated cross-sections agree very well with experimental results, in the whole energy and angular range.}, year = {2024}, type= {article}, }
- Carlos Guerra, Sarvesh Kumar, Fernando Aguilar-Galindo, Sergio DÃaz-Tendero, Ana I Lozano, Mónica Mendes, Juan C Oller, Paulo Limão-Vieira, Gustavo GarcÃa , “Total Electron Detachment and Induced Cationic Fragmentation Cross Sections for Superoxide Anion (O2-) Collisions with Benzene (C6H6) Molecules” International Journal of Molecular Sciences, vol. 23, 3 (2024).[Bibtex]
@article{ author = {Carlos Guerra, Sarvesh Kumar, Fernando Aguilar-Galindo, Sergio DÃaz-Tendero, Ana I Lozano, Mónica Mendes, Juan C Oller, Paulo Limão-Vieira, Gustavo GarcÃa }, title = {Total Electron Detachment and Induced Cationic Fragmentation Cross Sections for Superoxide Anion (O2-) Collisions with Benzene (C6H6) Molecules}, journal = {International Journal of Molecular Sciences}, volume = {23}, number = {3}, abstract = {In this study, novel experimental total electron detachment cross sections for O2− collisions with benzene molecules are reported for the impact energy range (10–1000 eV), as measured with a transmission beam apparatus. By analysing the positively charged species produced during the collision events, relative total ionisation cross sections were derived in the incident energy range of 160–900 eV. Relative partial ionisation cross sections for fragments with m/z ≤ 78 u were also given in this energy range. We also confirmed that heavier compounds (m/z > 78 u) formed for impact energies between 550 and 800 eV. In order to further our knowledge about the collision dynamics governing the fragmentation of such heavier molecular compounds, we performed molecular dynamics calculations within the framework of the Density Functional Theory (DFT). These results demonstrated that the fragmentation of these heavier compounds strongly supports the experimental evidence of m/z = 39–42, 50, 60 (u) cations formation, which contributed to the broad local maximum in the total ionisation observed from 550 to 800 eV. This work reveals the reactivity induced by molecular anions colliding with hydrocarbons at high energies, processes that can take place in the interstellar medium under various local conditions.}, year = {2024}, type= {article}, }
- Smita Ganguly, Dario Barreiro-Lage, Noelle Walsh, Bart Oostenrijk, Stacey L. Sorensen, Sergio DÃaz-Tendero, and Mathieu Gisselbrecht, “The origin of enhanced O2+ production from photoionized CO2 clusters” Communications Chemistry, vol. 5, 1 (2024).[Bibtex]
@article{ author = {Smita Ganguly, Dario Barreiro-Lage, Noelle Walsh, Bart Oostenrijk, Stacey L. Sorensen, Sergio DÃaz-Tendero, and Mathieu Gisselbrecht}, title = {The origin of enhanced O2+ production from photoionized CO2 clusters}, journal = {Communications Chemistry}, volume = {5}, number = {1}, abstract = {In this study, novel experimental total electron detachment cross sections for O2- collisions with benzene molecules are reported for the impact energy range (10-1000 eV), as measured with a transmission beam apparatus. By analysing the positively charged species produced during the collision events, relative total ionisation cross sections were derived in the incident energy range of 160-900 eV. Relative partial ionisation cross sections for fragments with m/z ≤ 78 u were also given in this energy range. We also confirmed that heavier compounds (m/z > 78 u) formed for impact energies between 550 and 800 eV. In order to further our knowledge about the collision dynamics governing the fragmentation of such heavier molecular compounds, we performed molecular dynamics calculations within the framework of the Density Functional Theory (DFT). These results demonstrated that the fragmentation of these heavier compounds strongly supports the experimental evidence of m/z = 39-42, 50, 60 (u) cations formation, which contributed to the broad local maximum in the total ionisation observed from 550 to 800 eV. This work reveals the reactivity induced by molecular anions colliding with hydrocarbons at high energies, processes that can take place in the interstellar medium under various local conditions. }, year = {2024}, type= {article}, }
- Yining Huo, Mónica K. Espinoza Cangahuala, Marcelo Goulart, Vicente Zamudio-Bayer, Markus Kubin, Martin Timm, J. Tobias Lau, Bernd von Issendorff, Ronnie Hoekstra, Shirin Faraji, and Thomas Schlathölter, “Soft-x-ray spectroscopy of coronene+ and (coronene+H)+ cations: The influence of hydrogenation on electronic structure and photofragmentation” Phys. Rev. A, vol. 106, 6 (2024).[Bibtex]
@article{ author = {Yining Huo, Mónica K. Espinoza Cangahuala, Marcelo Goulart, Vicente Zamudio-Bayer, Markus Kubin, Martin Timm, J. Tobias Lau, Bernd von Issendorff, Ronnie Hoekstra, Shirin Faraji, and Thomas Schlathölter}, title = {Soft-x-ray spectroscopy of coronene+ and (coronene+H)+ cations: The influence of hydrogenation on electronic structure and photofragmentation}, journal = {Phys. Rev. A}, volume = {106}, number = {6}, abstract = {We have studied soft-x-ray absorption in coronene and in singly hydrogenated coronene cations. Hydrogenation on the one hand closes the singly occupied molecular orbital of the coronene radical cation and thus decreases the reactivity of the molecule. On the other hand, the additional H atom breaks the coronene 𝐷6ℎ symmetry and exhibits a comparably small binding energy. The effect of single hydrogenation on soft-x-ray photoionization is therefore hard to predict. In our experiments, the mass selected polycyclic aromatic hydrocarbons' cations were stored in a cryogenic radio-frequency ion trap and exposed to monochromatic x rays with energies around the carbon 𝐾 edge. The partial photoion yields were recorded as a function of photon energy by means of time-of-flight mass spectrometry. The experimental data was compared to time-dependent density-functional theory calculations based on a short-range corrected functional. The combination of experiment and theory allowed for precise assignment of 1𝑠 excitations to the resonances in the spectra. We found that these resonant transitions as well as direct 1𝑠 ionization into the continuum could induce nondissociative ionization, H/H2 loss, as well as fragmentation of the carbon backbone. For multiple ionization, neutral hydrogen loss was found to compete with fission reactions where H+ or H2+ is released. H attachment was found to substantially decrease backbone fragmentation.}, year = {2024}, type= {article}, }
- M. D. Epée Epée, O. Motapon, N. Pop, F. Iacob, E. Roueff, I. F. Schneider, J. Zs Mezei, “Dissociative recombination and rotational transitions of D+2 in collisions with slow electrons” Monthly Notices of the Royal Astronomical Society, vol. 512, (2024).[Bibtex]
@article{ author = {M. D. Epée Epée, O. Motapon, N. Pop, F. Iacob, E. Roueff, I. F. Schneider, J. Zs Mezei}, title = {Dissociative recombination and rotational transitions of D+2 in collisions with slow electrons}, journal = {Monthly Notices of the Royal Astronomical Society}, volume = {512}, number = {}, abstract = {Rate coefficients for dissociative recombination and state-to-state rotational transitions of the D$_{2}^{+}$ ion induced by collisions with very low-energy electrons have been reported following our previous studies on HD+ and H$_{2}^{+}$. The same molecular structure data sets, excitations ($N_{i}^{+} \rightarrow$$N_{f}^{+}=N_{i}^{+}+2$ for $N_{i}^{+}=0$ to 10) and de-excitations ($N_{i}^{+}\rightarrow N_{f}^{+}=N_{i}^{+}-2$, for $N_{i}^{+}=2$ to 10) were used for collision energies ranging from 0.01 meV to 0.3 eV. Isotopic effects for dissociative recombination and rotational transitions of the vibrationally relaxed targets are presented.}, year = {2024}, type= {article}, }
- Sarvesh Kumar, José Romero, Michael Probst, Thana Maihom, Gustavo GarcÃa, Paulo Limão-Vieira , “Sensing the ortho Positions in C6Cl6 and C6H4Cl2 from Cl2- Formation upon Molecular Reduction ” Molecules, vol. 27, 15 (2024).[Bibtex]
@article{ author = {Sarvesh Kumar, José Romero, Michael Probst, Thana Maihom, Gustavo GarcÃa, Paulo Limão-Vieira }, title = {Sensing the ortho Positions in C6Cl6 and C6H4Cl2 from Cl2- Formation upon Molecular Reduction }, journal = {Molecules}, volume = {27}, number = {15}, abstract = {The geometrical effect of chlorine atom positions in polyatomic molecules after capturing a low-energy electron is shown to be a prevalent mechanism yielding Cl2−. In this work, we investigated hexachlorobenzene reduction in electron transfer experiments to determine the role of chlorine atom positions around the aromatic ring, and compared our results with those using ortho-, meta- and para-dichlorobenzene molecules. This was achieved by combining gas-phase experiments to determine the reaction threshold by means of mass spectrometry together with quantum chemical calculations. We also observed that Cl2− formation can only occur in 1,2-C6H4Cl2, where the two closest C–Cl bonds are cleaved while the chlorine atoms are brought together within the ring framework due to excess energy dissipation. These results show that a strong coupling between electronic and C–Cl bending motion is responsible for a positional isomeric effect, where molecular recognition is a determining factor in chlorine anion formation.}, year = {2024}, type= {article}, }
- Sándor Demes, François Lique, Alexandre Faure, Floris F S van der Tak, “An accurate set of H3O+ - H2 collisional rate coefficients for non-LTE modelling of warm interstellar clouds” Monthly Notices of the Royal Astronomical Society, vol. 518, 3 (2024).[Bibtex]
@article{ author = {Sándor Demes, François Lique, Alexandre Faure, Floris F S van der Tak}, title = {An accurate set of H3O+ - H2 collisional rate coefficients for non-LTE modelling of warm interstellar clouds}, journal = {Monthly Notices of the Royal Astronomical Society}, volume = {518}, number = {3}, abstract = {Hydronium (H3O+) was first detected in 1986 in interstellar molecular clouds. It was reported in many Galactic diffuse and dense regions, as well as in extragalactic sources. H3O+ plays a major role both in interstellar oxygen and water chemistry. However, despite the large number of H3O+ observations, its collisional excitation was investigated only partially. In this work, we study the state-to-state rotational (de-)excitation of ortho- and para-H3O+ in collisions both with ortho- and para-H2. The cross sections are calculated within the close-coupling formalism using a highly accurate potential energy surface developed for this system. The rate coefficients are computed up to a kinetic temperature of 300 K. Transitions between the lowest 21 rotation-inversion states were studied for para-H3O+, and the lowest 11 states for ortho-H3O+, i.e. all levels with rotational energies below 430 K (∼300 cm−1) are considered. In order to estimate the impact of the new rate coefficients on the astrophysical models for H3O+, radiative transfer calculations were also carried out. We have examined how the new collisional data affect the line intensities with respect to older data previously used for the interpretation of observations. By analysing all detected transitions we find that our new, accurate rate coefficients have a significant impact (typically within a factor of 2) on radiation temperatures, allowing more accurate estimation of column densities and relative abundances of hydronium, especially in warm molecular clouds, paving the path towards better interpretation of interstellar water and oxygen chemistry.}, year = {2024}, type= {article}, }
- Klavs Hansen and Henning Zettergren, “Clusters of Fullerenes: Structures and Dynamics” The Journal of Physical Chemistry A, vol. 126, 44 (2024).[Bibtex]
@article{ author = {Klavs Hansen and Henning Zettergren}, title = {Clusters of Fullerenes: Structures and Dynamics}, journal = {The Journal of Physical Chemistry A}, volume = {126}, number = {44}, abstract = {The geometric structures and reaction dynamics of clusters of carbon fullerene molecules are reviewed. The topics on structure cover the elementary building blocks, the interatomic and intermolecular potentials, and the geometric structures of the aggregates. The dynamics part describes the time development after excitation with laser light, in bimolecular collisions, and in collisions with high energy atomic ions. These reactions produce singly or multiply charged clusters, fragmented or intact fullerene monomers, and fusion products. The duration of the interaction time and the transferred energy are found to play determining roles for the nature of the products. Short interaction times and high energy excitation favor intramolecular reactions on excited potential energy surfaces, producing fused products, often with a strong release of the combined excess energy and heat of fusion. Clusters excited at low energies tend to disintegrate into intact fullerene molecules.}, year = {2024}, type= {article}, }
- Wissam Fakhardji, Péter Szabó, Magnus Gustafsson, “Direct method for MD simulations of collision-induced absorption: Application to an Ar-Xe gas mixture” Journal of Quantitative Spectroscopy and Radiative Transfer, vol. 276, 107926 (2021).[Bibtex]
@article{ author = {Wissam Fakhardji, Péter Szabó, Magnus Gustafsson}, title = {Direct method for MD simulations of collision-induced absorption: Application to an Ar-Xe gas mixture}, journal = {Journal of Quantitative Spectroscopy and Radiative Transfer}, volume = {276}, number = {107926}, abstract = {}, year = {2021}, type= {Article}, }
- S.D. Wiersma, A. Candian, M. Rapacioli, A. Petrignani, “IRMPD spectroscopy of a PAH cation using FELICE: The infrared spectrum and photodissociation of dibenzo[a,l]pyrene” Journal of Molecular Spectroscopy, vol. 382, 111545 (2021).[Bibtex]
@article{ author = {S.D. Wiersma, A. Candian, M. Rapacioli, A. Petrignani}, title = {IRMPD spectroscopy of a PAH cation using FELICE: The infrared spectrum and photodissociation of dibenzo[a,l]pyrene}, journal = {Journal of Molecular Spectroscopy}, volume = {382}, number = {111545}, abstract = {}, year = {2021}, type= {Article}, }
- Michael Gatchell, João Ameixa, MingChao Ji, Mark H. Stockett, Ansgar Simonsson, Stephan Denifl, Henrik Cederquist, Henning T. Schmidt and Henning Zettergren , “Survival of polycyclic aromatic hydrocarbon knockout fragments in the interstellar medium” Nature Communications, vol. 12, 6646 (2021).[Bibtex]
@article{ author = {Michael Gatchell, João Ameixa, MingChao Ji, Mark H. Stockett, Ansgar Simonsson, Stephan Denifl, Henrik Cederquist, Henning T. Schmidt and Henning Zettergren }, title = {Survival of polycyclic aromatic hydrocarbon knockout fragments in the interstellar medium}, journal = {Nature Communications}, volume = {12}, number = {6646}, abstract = {Laboratory studies play a crucial role in understanding the chemical nature of the interstellar medium (ISM), but the disconnect between experimental timescales and the timescales of reactions in space can make a direct comparison between observations, laboratory, and model results difficult. Here we study the survival of reactive fragments of the polycyclic aromatic hydrocarbon (PAH) coronene, where individual C atoms have been knocked out of the molecules in hard collisions with He atoms at stellar wind and supernova shockwave velocities. Ionic fragments are stored in the DESIREE cryogenic ion-beam storage ring where we investigate their decay for up to one second. After 10 ms the initially hot stored ions have cooled enough so that spontaneous dissociation no longer takes place at a measurable rate; a majority of the fragments remain intact and will continue to do so indefinitely in isolation. Our findings show that defective PAHs formed in energetic collisions with heavy particles may survive at thermal equilibrium in the interstellar medium indefinitely, and could play an important role in the chemistry in there, due to their increased reactivity compared to intact or photo-fragmented PAHs.}, year = {2021}, type= {Article}, }
- Kevin M. Hickson, Somnath Bhowmick, Yury V. Suleimanov, João Brandão and Daniela V. Coelho, “Experimental and theoretical studies of the gas-phase reactions of O(1D) with H2O and D2O at low temperature” Physical Chemistry Chemical Physics, vol. 23, 45 (2021).[Bibtex]
@article{ author = {Kevin M. Hickson, Somnath Bhowmick, Yury V. Suleimanov, João Brandão and Daniela V. Coelho}, title = {Experimental and theoretical studies of the gas-phase reactions of O(1D) with H2O and D2O at low temperature}, journal = {Physical Chemistry Chemical Physics}, volume = {23}, number = {45}, abstract = {Here we report the results of an experimental and theoretical study of the gas-phase reactions between O(1D) and H2O and O(1D) and D2O at room temperature and below. On the experimental side{,} the kinetics of these reactions have been investigated over the 50–127 K range using a continuous flow Laval nozzle apparatus{,} coupled with pulsed laser photolysis and pulsed laser induced fluorescence for the production and detection of O(1D) atoms respectively. Experiments were also performed at 296 K in the absence of a Laval nozzle. On the theoretical side{,} the existing full-dimensional ground X 1A potential energy surface for the H2O2 system involved in this process has been reinvestigated and enhanced to provide a better description of the barrierless H-atom abstraction pathway. Based on this enhanced potential energy surface{,} quasiclassical trajectory calculations and ring polymer molecular dynamics simulations have been performed to obtain low temperature rate constants. The measured and calculated rate constants display similar behaviour above 100 K{,} showing little or no variation as a function of temperature. Below 100 K{,} the experimental rate constants increase dramatically{,} in contrast to the essentially temperature independent theoretical values. The possible origins of the divergence between experiment and theory at low temperatures are discussed.}, year = {2021}, type= {Article}, }
- Roberto Linguerri, Emelie Olsson, Gunnar Nyman, Majdi Hochlaf*, John H. D. Eland*, and Raimund Feifel*, “Unimolecular Double Photoionization-Induced Processes in Iron Pentacarbonyl” Inorganic Chemistry, vol. 60, 23 (2021).[Bibtex]
@article{ author = { Roberto Linguerri, Emelie Olsson, Gunnar Nyman, Majdi Hochlaf*, John H. D. Eland*, and Raimund Feifel*}, title = {Unimolecular Double Photoionization-Induced Processes in Iron Pentacarbonyl}, journal = {Inorganic Chemistry}, volume = {60}, number = {23}, abstract = {}, year = {2021}, type= {Article}, }
- Mathias Poline, Arnaud Dochain, Stefan Rosén, Jon Grumer, MingChao Ji, Gustav Eklund, Ansgar Simonsson, Peter Reinhed, Mikael Blom, Nicholas S. Shuman, Shaun G. Ard, Albert A. Viggiano, Mats Larsson, Henrik Cederquist, Henning T. Schmidt, Henning Zettergren, Xavier Urbain, Paul S. Barklem and Richard D. Thomas, “Mutual neutralisation of O+ with O-: investigation of the role of metastable ions in a combined experimental and theoretical study ” Physical Chemistry Chemical Physics, vol. 23, 43 (2021).[Bibtex]
@article{ author = {Mathias Poline, Arnaud Dochain, Stefan Rosén, Jon Grumer, MingChao Ji, Gustav Eklund, Ansgar Simonsson, Peter Reinhed, Mikael Blom, Nicholas S. Shuman, Shaun G. Ard, Albert A. Viggiano, Mats Larsson, Henrik Cederquist, Henning T. Schmidt, Henning Zettergren, Xavier Urbain, Paul S. Barklem and Richard D. Thomas}, title = {Mutual neutralisation of O+ with O-: investigation of the role of metastable ions in a combined experimental and theoretical study }, journal = {Physical Chemistry Chemical Physics}, volume = {23}, number = {43}, abstract = {The mutual neutralisation of O+ with O− has been studied in a double ion-beam storage ring with combined merged-beams{,} imaging and timing techniques. Branching ratios were measured at the collision energies of 55{,} 75 and 170 (± 15) meV{,} and found to be in good agreement with previous single-pass merged-beams experimental results at 7 meV collision energy. Several previously unidentified spectral features were found to correspond to mutual neutralisation channels of the first metastable state of the cation (O+(2Do){,} τ ≈ 3.6 hours){,} while no contributions from the second metastable state (O+(2Po){,} τ ≈ 5 seconds) were observed. Theoretical calculations were performed using the multi-channel Landau–Zener model combined with the anion centered asymptotic method{,} and gave good agreement with several experimentally observed channels{,} but could not describe well observed contributions from the O+(2Do) metastable state as well as channels involving the O(3s 5So) state.}, year = {2021}, type= {Article}, }
- L. H. Yang, J. M. Gong, A. Sulyok, M. Menyhárd, G. Sáfrán, K. TÅ‘kési, B. Dabe and Z. J. Ding, “Optical properties of amorphous carbon determined by reflection electron energy loss spectroscopy spectra” Physical Chemistry Chemical Physics, vol. 23, 44 (2021).[Bibtex]
@article{ author = {L. H. Yang, J. M. Gong, A. Sulyok, M. Menyhárd, G. Sáfrán, K. TÅ‘kési, B. Dabe and Z. J. Ding}, title = {Optical properties of amorphous carbon determined by reflection electron energy loss spectroscopy spectra}, journal = {Physical Chemistry Chemical Physics}, volume = {23}, number = {44}, abstract = {We present the combined experimental and theoretical investigations of the optical properties of amorphous carbon. The reflection electron energy loss spectra (REELS) spectra of carbon were measured using a cylindrical mirror analyzer under ultrahigh vacuum conditions at primary electron energies of 750{,} 1000 and 1300 eV. The energy loss function and thereby the refractive index n and the extinction coefficient k were determined from these REELS spectra in a wide loss energy range of 2–200 eV by applying our reverse Monte Carlo method. The high accuracy of the obtained optical constants is justified with the ps- and f-sum rules. We found that our present optical constants of amorphous carbon fulfill the sum rules with the highest accuracy compared with the previously published data. Therefore{,} we highly recommend to replace the previous data with the present ones for practical applications. Moreover{,} we present the atomic scattering factors of amorphous carbon obtained from the dielectric function to predict its optical constants at a given density.}, year = {2021}, type= {Article}, }
- Patrick Rousseau, Jesús González-Vázquez, Dariusz G. Piekarski, Janina Kopyra, Alicja Domaracka, Manuel AlcamíLamri, Adoui Bernd A. Huber, Sergio Díaz-Tendero and Fernando Martín, “Timing of charge migration in betaine by impact of fast atomic ions” Science Advances, vol. 7, 40 (2021).[Bibtex]
@article{ author = {Patrick Rousseau, Jesús González-Vázquez, Dariusz G. Piekarski, Janina Kopyra, Alicja Domaracka, Manuel AlcamíLamri, Adoui Bernd A. Huber, Sergio Díaz-Tendero and Fernando Martín}, title = {Timing of charge migration in betaine by impact of fast atomic ions}, journal = {Science Advances}, volume = {7}, number = {40}, abstract = {Intramolecular charge migration induced by fast highly charged atomic ions in the betaine zwitterion is ultrafast and adiabatic. The way molecules break after ion bombardment is intimately related to the early electron dynamics generated in the system, in particular, charge (or electron) migration. We exploit the natural positive-negative charge splitting in the zwitterionic molecule betaine to selectively induce double electron removal from its negatively charged side by impact of fast O6+ ions. The loss of two electrons in this localized region of the molecular skeleton triggers a competition between direct Coulomb explosion and charge migration that is examined to obtain temporal information from ion-ion coincident measurements and nonadiabatic molecular dynamics calculations. We find a charge migration time, from one end of the molecule to the other, of approximately 20 to 40 femtoseconds. This migration time is longer than that observed in molecules irradiated by ultrashort light pulses and is the consequence of charge migration being driven by adiabatic nuclear dynamics in the ground state of the molecular dication.}, year = {2021}, type= {Article}, }
- Wen Li, Oksana Kavatsyuk, Wessel Douma, Xin Wang, Ronnie Hoekstra, Dennis Mayer, Matthew S. Robinson, Markus Gühr, Mathieu Lalande, Marwa Abdelmouleh, Michal Ryszka, Jean Christophe Poully and Thomas Schlathölter, “Multiple valence electron detachment following Auger decay of inner-shell vacancies in gas-phase DNA ” Chemical Science, vol. 12, (2021).[Bibtex]
@article{ author = {Wen Li, Oksana Kavatsyuk, Wessel Douma, Xin Wang, Ronnie Hoekstra, Dennis Mayer, Matthew S. Robinson, Markus Gühr, Mathieu Lalande, Marwa Abdelmouleh, Michal Ryszka, Jean Christophe Poully and Thomas Schlathölter}, title = {Multiple valence electron detachment following Auger decay of inner-shell vacancies in gas-phase DNA }, journal = {Chemical Science}, volume = {12}, number = {}, abstract = {}, year = {2021}, type= {Article}, }
- Lassi Pihlava, Johannes Niskanen, Kuno Kooser, Christian Stråhlman, Sylvain Maclot, Antti Kivimäki and Edwin Kukka , “Photodissociation dynamics of halogenated aromatic molecules: the case of core-ionized tetrabromothiophene” Physical Chemistry Chemical Physics, vol. 23, 37 (2021).[Bibtex]
@article{ author = {Lassi Pihlava, Johannes Niskanen, Kuno Kooser, Christian Stråhlman, Sylvain Maclot, Antti Kivimäki and Edwin Kukka }, title = {Photodissociation dynamics of halogenated aromatic molecules: the case of core-ionized tetrabromothiophene}, journal = {Physical Chemistry Chemical Physics}, volume = {23}, number = {37}, abstract = {We studied the gas-phase photodissociation of a fully halogenated aromatic molecule{,} tetrabromothiophene{,} upon core–shell ionization by using synchrotron radiation and energy-resolved multiparticle coincidence spectroscopy. Photodynamics was initiated by the selective soft X-ray ionization of three elements – C{,} S{,} and Br – leading to the formation of dicationic states by Auger decay. From a detailed study of photodissociation upon Br 3d ionization{,} we formulate a general fragmentation scheme{,} where dissociation into neutral fragments and a pair of cations prevails{,} but dicationic species are also produced. We conclude that dicationic tetrabromothiophene typically undergoes deferred charge separation (with one of the ions being often Br+) that may be followed by secondary dissociation steps{,} depending on the available internal energy of the parent dication. Observations suggest that the ejection of neutral bromine atoms as the first step of deferred charge separation is a prevailing feature in dicationic dissociation{,} although sometimes in this step the C–Br bonds appear to remain intact and the thiophene ring is broken instead. Ionization-site-specific effects are observed particularly in doubly charged fragments and as large differences in the yields of the intact parent dication. We interpret these effects{,} using first-principles calculations and molecular dynamics simulations of core-hole states{,} as likely caused by the geometry changes during the core-hole lifetime.}, year = {2021}, type= {Article}, }
- S. Kumar and D. Duflot and S.V. Hoffmann and N.C. Jones and P. Bolognesi and L. Carlini and R. Richter and L. Avaldi and M.J. Brunger and P. Limão-Vieira, “A combined experimental and theoretical study of the lowest-lying valence, Rydberg and ionic electronic states of 2,4,6-trichloroanisole” Journal of Quantitative Spectroscopy and Radiative Transfer, vol. 271, (2021).[Bibtex]
@article{ author = {S. Kumar and D. Duflot and S.V. Hoffmann and N.C. Jones and P. Bolognesi and L. Carlini and R. Richter and L. Avaldi and M.J. Brunger and P. Limão-Vieira}, title = {A combined experimental and theoretical study of the lowest-lying valence, Rydberg and ionic electronic states of 2,4,6-trichloroanisole}, journal = {Journal of Quantitative Spectroscopy and Radiative Transfer}, volume = {271}, number = {}, abstract = {We investigate for the first time the gas-phase lowest-lying valence, Rydberg and ionic electronic states of 2,4,6-trichloroanisole (TCA) using synchrotron radiation for photoabsorption and photoelectron spectroscopy. The high-resolution vacuum ultraviolet photoabsorption spectrum, in the 4.0–10.8 eV energy-range, has been measured with absolute photoabsorption cross-sections and, thanks to novel ab initio calculations of the vertical energies and oscillator strengths, an assignment of the electronic transitions is comprehensively reported. The assignment of weak vibrational features in the absorption bands of TCA reveal that the ring and C–Cl stretching modes are mainly active. In the photoelectron spectrum the lowest 18 ionic bands, between 8 and 30 eV, have been observed and assigned using the first set of calculated valence and outer valence vertical ionisation energies. Finally, the measured absolute photoabsorption cross sections have also been used to estimate the photolysis lifetime of TCA in the upper stratosphere (20–50 km).}, year = {2021}, type= {Article}, }
- Maria Hoflund, Jasper Peschel, Marius Plach, Hugo Dacasa, Kévin Veyrinas, Eric Constant, Peter Smorenburg, Hampus Wikmark, Sylvain Maclot, Chen Guo, Cord Arnold, Anne L'Huillier et al., “Focusing Properties of High-Order Harmonics” Ultrafast Science, vol. 2021, 9797453 (2021).[Bibtex]
@article{ author = {Maria Hoflund, Jasper Peschel, Marius Plach, Hugo Dacasa, Kévin Veyrinas, Eric Constant, Peter Smorenburg, Hampus Wikmark, Sylvain Maclot, Chen Guo, Cord Arnold, Anne L'Huillier et al.}, title = {Focusing Properties of High-Order Harmonics}, journal = {Ultrafast Science}, volume = {2021}, number = {9797453}, abstract = {}, year = {2021}, type= {Article}, }
- Thomas F. M. Luxford, Jaroslav KoÄišek, Lukas Tiefenthaler & Pamir Nag, “Dissociative attachment of low-energy electrons to acetonitrile” The European Physical Journal D , vol. 75, 8 (2021).[Bibtex]
@article{ author = {Thomas F. M. Luxford, Jaroslav KoÄišek, Lukas Tiefenthaler & Pamir Nag}, title = {Dissociative attachment of low-energy electrons to acetonitrile}, journal = {The European Physical Journal D }, volume = {75}, number = {8}, abstract = {We experimentally probed the low-energy electron-induced dissociation of acetonitrile and acetonitrile-$$\hbox {d}_3$$and performed density functional theory calculations to support the experimental results. The previous studies on electron attachment to acetonitrile presented a number of contradictory findings, which we aimed to resolve in the present study. We observed the formation of $$\hbox {H}^-$$, $$\hbox {CH}_2^-$$, $$\hbox {CH}_3^-$$, $$\hbox {CN}^-$$, $$\hbox {CCN}^-$$, $$\hbox {CHCN}^-$$and $$\hbox {CH}_2 \hbox {CN}^-$$anions and the corresponding deuterated fragments for acetonitrile-$$\hbox {d}_3$$by dissociative electron attachment, and measured ion yields curves of each fragment. We saw no evidence for associative electron attachment to form the parent ion in these measurements. We also have measured the kinetic energy and angular distribution of selected fragments using a velocity map imaging (VMI) spectrometer.}, year = {2021}, type= {Article}, }
- Darío Barreiro-Lage, Paola Bolognesi*, Jacopo Chiarinelli, Robert Richter, Henning Zettergren, Mark H. Stockett, Laura Carlini, Sergio Diaz-Tendero*, and Lorenzo Avaldi, “"Smart Decomposition" of Cyclic Alanine-Alanine Dipeptide by VUV Radiation: A Seed for the Synthesis of Biologically Relevant Species” The Journal of Physical Chemistry Letters, vol. 12, 30 (2021).[Bibtex]
@article{ author = {Darío Barreiro-Lage, Paola Bolognesi*, Jacopo Chiarinelli, Robert Richter, Henning Zettergren, Mark H. Stockett, Laura Carlini, Sergio Diaz-Tendero*, and Lorenzo Avaldi}, title = {"Smart Decomposition" of Cyclic Alanine-Alanine Dipeptide by VUV Radiation: A Seed for the Synthesis of Biologically Relevant Species}, journal = {The Journal of Physical Chemistry Letters}, volume = {12}, number = {30}, abstract = {}, year = {2021}, type= {Article}, }
- Péter Szabó*, Szabolcs Góger and Magnus Gustafsson*, “Formation of the BeH+ and BeD+ Molecules in Be+ + H/D Collisions Through Radiative Association” Frontiers in Astronomy and Space Sciences, vol. 8, (2021).[Bibtex]
@article{ author = {Péter Szabó*, Szabolcs Góger and Magnus Gustafsson*}, title = {Formation of the BeH+ and BeD+ Molecules in Be+ + H/D Collisions Through Radiative Association}, journal = {Frontiers in Astronomy and Space Sciences}, volume = {8}, number = {}, abstract = {Cross sections and rate coefficients for the formation of BeH+ and BeD+ molecules in Be+ + H/D collisions through radiative association are calculated using quantum mechanical perturbation theory and Breit-Wigner theory. The local thermodynamic equilibrium limit of the molecule formation is also studied, since the process is also relevant in environments with high-density and/or strong radiation fields. The obtained rate coefficients may facilitate the kinetic modelling of BeH+/BeD+ production in astrochemical environments as well as the corrosion chemistry of thermonuclear fusion reactors}, year = {2021}, type= {Article}, }
- Linda Giacomozzi, Christina Kjær, Steen Brøndsted Nielsen, Eleanor K. Ashworth, James N. Bull, and Mark H. Stockett, “Non-statistical fragmentation in photo-activated flavin mononucleotide anions” The Journal of Chemical Physics, vol. 155, 4 (2021).[Bibtex]
@article{ author = {Linda Giacomozzi, Christina Kjær, Steen Brøndsted Nielsen, Eleanor K. Ashworth, James N. Bull, and Mark H. Stockett}, title = {Non-statistical fragmentation in photo-activated flavin mononucleotide anions}, journal = {The Journal of Chemical Physics}, volume = {155}, number = {4}, abstract = {}, year = {2021}, type= {Article}, }
- Janina Kopyra, Paulina Wierzbicka, Adrian Tulwin, Guillaume Thiam, Ilko Bald, Franck Rabilloud and Hassan Abdoul-Carime, “Experimental and Theoretical Studies of Dissociative Electron Attachment to Metabolites Oxaloacetic and Citric Acids” International Journal of Molecular Sciences, vol. 22, 7676 (2021).[Bibtex]
@article{ author = {Janina Kopyra, Paulina Wierzbicka, Adrian Tulwin, Guillaume Thiam, Ilko Bald, Franck Rabilloud and Hassan Abdoul-Carime}, title = {Experimental and Theoretical Studies of Dissociative Electron Attachment to Metabolites Oxaloacetic and Citric Acids}, journal = {International Journal of Molecular Sciences}, volume = {22}, number = {7676}, abstract = {In this contribution the dissociative electron attachment to metabolites found in aerobic organisms, namely oxaloacetic and citric acids, was studied both experimentally by means of a crossed-beam setup and theoretically through density functional theory calculations. Prominent negative ion resonances from both compounds are observed peaking below 0.5 eV resulting in intense formation of fragment anions associated with a decomposition of the carboxyl groups. In addition, resonances at higher energies (3–9 eV) are observed exclusively from the decomposition of the oxaloacetic acid. These fragments are generated with considerably smaller intensities. The striking findings of our calculations indicate the different mechanism by which the near 0 eV electron is trapped by the precursor molecule to form the transitory negative ion prior to dissociation. For the oxaloacetic acid, the transitory anion arises from the capture of the electron directly into some valence states, while, for the citric acid, dipole- or multipole-bound states mediate the transition into the valence states. What is also of high importance is that both compounds while undergoing DEA reactions generate highly reactive neutral species that can lead to severe cell damage in a biological environment.}, year = {2021}, type= {Article}, }
- Giuseppe Mattioli, Lorenzo Avaldi, Paola Bolognesi, John D. Bozek, Mattea C. Castrovilli, Jacopo Chiarinelli, Alicja Domaracka, Suvasthika Indrajith, Sylvain Maclot, Aleksandar R. Milosavljević, Chiara Nicolafrancesco, Christophe Nicolas & Patrick Rousseau, “Water-biomolecule clusters studied by photoemission spectroscopy and multilevel atomistic simulations: hydration or solvation?” Physical Chemistry Chemical Physics, vol. 23, 28 (2021).[Bibtex]
@article{ author = {Giuseppe Mattioli, Lorenzo Avaldi, Paola Bolognesi, John D. Bozek, Mattea C. Castrovilli, Jacopo Chiarinelli, Alicja Domaracka, Suvasthika Indrajith, Sylvain Maclot, Aleksandar R. Milosavljević, Chiara Nicolafrancesco, Christophe Nicolas & Patrick Rousseau}, title = {Water-biomolecule clusters studied by photoemission spectroscopy and multilevel atomistic simulations: hydration or solvation?}, journal = {Physical Chemistry Chemical Physics}, volume = {23}, number = {28}, abstract = {The properties of mixed water–uracil nanoaggregates have been probed by core electron–photoemission measurements to investigate supramolecular assembly in the gas phase driven by weak interactions. The interpretation of the measurements has been assisted by multilevel atomistic simulations{,} based on semi-empirical tight-binding and DFT-based methods. Our protocol established a positive-feedback loop between experimental and computational techniques{,} which has enabled a sound and detailed atomistic description of such complex heterogeneous molecular aggregates. Among biomolecules{,} uracil offers interesting and generalized skeletal features; its structure encompasses an alternation of hydrophilic H-bond donor and acceptor sites and hydrophobic moieties{,} typical in biomolecular systems{,} that induces a supramolecular core–shell-like organization of the mixed clusters with a water core and an uracil shell. This structure is far from typical models of both solid-state hydration{,} with water molecules in defined positions{,} or liquid solvation{,} where disconnected uracil molecules are completely surrounded by water.}, year = {2021}, type= {Article}, }
- Mark H. Stockett, Lorenzo Avaldi, Paola Bolognesi, James N. Bull, Laura Carlini, Eduardo Carrascosa, Jacopo Chiarinelli, Robert Richter, and Henning Zettergren , “Competitive Dehydrogenation and Backbone Fragmentation of Superhydrogenated PAHs: A Laboratory Study” The Astrophysical Journal, vol. 913, 1 (2021).[Bibtex]
@article{ author = {Mark H. Stockett, Lorenzo Avaldi, Paola Bolognesi, James N. Bull, Laura Carlini, Eduardo Carrascosa, Jacopo Chiarinelli, Robert Richter, and Henning Zettergren }, title = {Competitive Dehydrogenation and Backbone Fragmentation of Superhydrogenated PAHs: A Laboratory Study}, journal = {The Astrophysical Journal}, volume = {913}, number = {1}, abstract = {}, year = {2021}, type= {Article}, }
- Henning Zettergren*, Alicja Domaracka, Thomas Schlathölter, et al., “Roadmap on dynamics of molecules and clusters in the gas phase” The European Physical Journal D, vol. 75, 125 (2021).[Bibtex]
@article{ author = {Henning Zettergren*, Alicja Domaracka, Thomas Schlathölter, et al.}, title = {Roadmap on dynamics of molecules and clusters in the gas phase}, journal = {The European Physical Journal D}, volume = {75}, number = {125}, abstract = {}, year = {2021}, type= {Article}, }
- Xin Wang, Sivasudhan Rathnachalam, Klaas Bijlsma,Wen Li, Ronnie Hoekstra, Markus Kubin, Martin Timm, Bernd von Issendorff, Vicente Zamudio-Bayer, J. Tobias Lau, Shirin Faraji and Thomas Schlathölter, “Site-selective soft X-ray absorption as a tool to study protonation and electronic structure of gas-phase DNA” Physical Chemistry Chemical Physics, vol. 23, (2021).[Bibtex]
@article{ author = {Xin Wang, Sivasudhan Rathnachalam, Klaas Bijlsma,Wen Li, Ronnie Hoekstra, Markus Kubin, Martin Timm, Bernd von Issendorff, Vicente Zamudio-Bayer, J. Tobias Lau, Shirin Faraji and Thomas Schlathölter}, title = {Site-selective soft X-ray absorption as a tool to study protonation and electronic structure of gas-phase DNA}, journal = {Physical Chemistry Chemical Physics}, volume = {23}, number = {}, abstract = {The conformation and the electronic structure of gas-phase oligonucleotides depends strongly on the protonation site. 5′-d(FUAG) can either be protonated at the A-N1 or at the G-N7 position. We have stored protonated 5′-d(FUAG) cations in a cryogenic ion trap held at about 20 K. To identify the protonation site and the corresponding electronic structure, we have employed soft X-ray absorption spectroscopy at the nitrogen K-edge. The obtained spectra were interpreted by comparison to time-dependent density functional theory calculations using a short-range exchange correlation functional. Despite the fact that guanine has a significantly higher proton affinity than adenine, the agreement between experiment and theory is better for the A-N1 protonated system. Furthermore, an inverse site sensitivity is observed in which the yield of the nucleobase fragments that contain the absorption site appears substantially reduced, which could be explained by non-statistical fragmentation processes, localized on the photoabsorbing nucleobase.}, year = {2021}, type= {Article, selected as 2021 PCCP HOT Article}, }
- Klavs Hansen and Henning Zettergren , “Chapter 9 Clusters of Fullerenes” The Royal Society of Chemistry, vol. , (2021).[Bibtex]
@article{ author = {Klavs Hansen and Henning Zettergren }, title = {Chapter 9 Clusters of Fullerenes}, journal = {The Royal Society of Chemistry}, volume = {}, number = {}, abstract = {The structure and dynamics of clusters of the all-carbon fullerene molecules are reviewed. After a brief overview of the properties of the individual fullerene molecules{,} the experimentally determined structures and the theoretical interaction potentials describing the cluster properties are reviewed. The dynamics of fullerene–fullerene molecule interaction after exposure of clusters to laser excitation{,} in bi-molecular collisions and after exposure of clusters to high energy ion beams is then reviewed. These show that the end products may be (multiply) charged clusters{,} fragmented or intact fullerene monomers or a wide range of fusion products{,} depending on how the excitation energy is transferred to the clusters and the amount of it.}, year = {2021}, type= {Book}, }
- N. Pop, F. Iacob, S. Niyonzima, A. Abdoulanziz, V. Laporta, D. Reiter, I.F. Schneiderd, J.Zs. Mezei, “Reactive collisions between electrons and BeT+: Complete set of thermal rate coefficients up to 5000 K” Atomic Data and Nuclear Data Tables, vol. 139, 101414 (2021).[Bibtex]
@article{ author = {N. Pop, F. Iacob, S. Niyonzima, A. Abdoulanziz, V. Laporta, D. Reiter, I.F. Schneiderd, J.Zs. Mezei}, title = {Reactive collisions between electrons and BeT+: Complete set of thermal rate coefficients up to 5000 K}, journal = {Atomic Data and Nuclear Data Tables}, volume = {139}, number = {101414}, abstract = {}, year = {2021}, type= {Article}, }
- J Odavić and P Mali, “Random matrix ensembles in hyperchaotic classical dissipative dynamic systems” Journal of Statistical Mechanics: Theory and Experiment, vol. 2021, 4 (2021).[Bibtex]
@article{ author = {J Odavić and P Mali}, title = {Random matrix ensembles in hyperchaotic classical dissipative dynamic systems}, journal = {Journal of Statistical Mechanics: Theory and Experiment}, volume = {2021}, number = {4}, abstract = {We study the statistical fluctuations of Lyapunov exponents in the discrete version of the non-integrable perturbed sine-Gordon equation, the dissipative AC- and DC-driven Frenkel–Kontorova model. Our analysis shows that the fluctuations of the exponent spacings in the strictly overdamped limit, which is nonchaotic, conform to an uncorrelated Poisson distribution. By studying the spatiotemporal dynamics, we relate the emergence of the Poissonian statistics to Middleton’s no-passing rule. Next, by scanning values of the DC drive and the particle mass, we identify several parameter regions for which this one-dimensional model exhibits hyperchaotic behavior. Furthermore, in the hyperchaotic regime where roughly fifty percent of the exponents are positive, the fluctuations exhibit features of the correlated universal statistics of the Gaussian orthogonal ensemble (GOE). Due to the dissipative nature of the dynamics, we find that the match between the Lyapunov spectrum statistics and the universal statistics of GOE is not complete. Finally, we present evidence supporting the existence of the Tracy–Widom distribution in the fluctuation statistics of the largest Lyapunov exponent.}, year = {2021}, type= {Article}, }
- Majdi Hochlaf, Roberto Linguerri, Mohamed Cheraki, Tarek Ayari, Ridha Ben Said, Raimund Feifel and Gilberte Chambaud, “S2O2q+ (q = 0, 1, and 2) Molecular Systems: Characterization and Atmospheric Planetary Implications” The Journal of Physical Chemistry A, vol. 125, 9 (2021).[Bibtex]
@article{ author = {Majdi Hochlaf, Roberto Linguerri, Mohamed Cheraki, Tarek Ayari, Ridha Ben Said, Raimund Feifel and Gilberte Chambaud}, title = {S2O2q+ (q = 0, 1, and 2) Molecular Systems: Characterization and Atmospheric Planetary Implications}, journal = {The Journal of Physical Chemistry A}, volume = {125}, number = {9}, abstract = {We use accurate ab initio methodologies at the coupled cluster level ((R)CCSD(T)) and its explicitly correlated version ((R)CCSD(T)-F12) to investigate the electronic structure, relative stability, and spectroscopy of the stable isomers of the [S2O2] system and of some of its cations and dications, with a special focus on the most relevant isomers that could be involved in terrestrial and planetary atmospheres. This work identifies several stable isomers (10 neutral, 8 cationic, and 5 dicationic), including trigonal-OSSO, cis-OSSO, and cyc-OSSO. For all these isomers, we calculated geometric parameters, fragmentation energies, and simple and double ionization energies of the neutral species. Several structures are identified for the first time, especially for the ionic species. Computations show that in addition to cis-OSSO and trans-OSSO proposed for the absorption in the near-UV spectrum of the Venusian atmosphere other S2O2, S2O2+, and S2O22+ species may contribute. Moreover, the characterization of the stability of singly and doubly charged S2O2 entities can also be used for their identification by mass spectrometry and UV spectroscopy in the laboratory or in planetary atmospheres. In sum, the quest for the main UV absorber in Venus’ atmosphere is not over, since the physical chemistry of sulfur oxides in Venus’ atmosphere is far from being understood.}, year = {2021}, type= {Article}, }
- Néstor F. Aguirre, Sergio DÃaz-Tendero, Paul-Antoine Hervieux, Manuel AlcamÃ, Marin Chabot, Karine Béroff & Fernando MartÃn , “Charge and energy sharing in the fragmentation of astrophysically relevant carbon clusters” Theoretical Chemistry Accounts, vol. 140, (2021).[Bibtex]
@article{ author = {Néstor F. Aguirre, Sergio DÃaz-Tendero, Paul-Antoine Hervieux, Manuel AlcamÃ, Marin Chabot, Karine Béroff & Fernando MartÃn }, title = {Charge and energy sharing in the fragmentation of astrophysically relevant carbon clusters}, journal = {Theoretical Chemistry Accounts}, volume = {140}, number = {}, abstract = {The breakup of a molecule following a fast collision with an atom in gas phase can be understood as resulting from two steps. In the first step, the atom transfers energy to the molecule, which is thus electronically and vibrationally excited. In the second step, the molecule decays leading to different fragments, while the initial charge, energy, and angular momentum are conserved. Here, we demonstrate that, by maximizing the entropy of the system under these conservation laws, it is possible to reproduce the fragmentation yields resulting from collision experiments. In particular, our model is applied to investigate fragmentation of excited neutral and singly charged carbon clusters and mono-hydrogenated carbon clusters. These species are commonly exposed to energetic ionizing radiation in the interstellar medium, so understanding the key aspects of their fragmentation, in particular the way energy and charge are shared in the process, can be relevant to get a deeper insight on the evolution of carbonaceous species in the universe.}, year = {2021}, type= {Article}, }
- A. Abdoulanziz, C. Argentin, V. Laporta, K. Chakrabarti, A. Bultel, J. Tennyson, I. F. Schneider and J. Zs. Mezei1, “Low-energy electron impact dissociative recombination and vibrational transitions of N2+” Journal of Applied Physics, vol. 129, 5 (2021).[Bibtex]
@article{ author = {A. Abdoulanziz, C. Argentin, V. Laporta, K. Chakrabarti, A. Bultel, J. Tennyson, I. F. Schneider and J. Zs. Mezei1}, title = {Low-energy electron impact dissociative recombination and vibrational transitions of N2+}, journal = {Journal of Applied Physics}, volume = {129}, number = {5}, abstract = {}, year = {2021}, type= {Article}, }
- Felix Laimer, Fabio Zappa, Paul Scheier, and Michael Gatchell, “Multiply Charged Helium Droplet Anions” Chemistry–A European Journal, vol. 27, 25 (2021).[Bibtex]
@article{ author = {Felix Laimer, Fabio Zappa, Paul Scheier, and Michael Gatchell}, title = {Multiply Charged Helium Droplet Anions}, journal = {Chemistry–A European Journal}, volume = {27}, number = {25}, abstract = {The detection of multiply charged helium droplet anions is reported for the first time. By ionizing droplets of superfluid helium with low energy electrons (up to 25 eV), it was possible to produce droplets containing up to five negative charges, which remain intact on the timescale of the experiment. The appearance sizes for different charge states are determined and are found to be orders of magnitude larger than for the equivalent cationic droplets, starting at 4 million He atoms for dianions. Droplets with He*− as charge carriers show signs of being metastable, but this effect is quenched by the pickup of water molecules.}, year = {2021}, type= {Article}, }
- Martini, P; Albertini, S; Laimer, F; Meyer, M; Gatchell, M; Echt, O; Zappa, F; Scheier, P, “Splashing of Large Helium Nanodroplets upon Surface Collisions” Physical Review Letters, vol. 127, (2021).[Bibtex]
@article{ author = {Martini, P; Albertini, S; Laimer, F; Meyer, M; Gatchell, M; Echt, O; Zappa, F; Scheier, P}, title = {Splashing of Large Helium Nanodroplets upon Surface Collisions}, journal = {Physical Review Letters}, volume = {127}, number = {}, abstract = {}, year = {2021}, type= {paper1}, }
- Carlos Guerra, Sarvesh Kumar, Fernando Aguilar-Galindo, Sergio DÃaz-Tendero, Ana Isabel Lozano, Mónica Mendes, Paulo Limão-Vieira, Gustavo Garcia, “Unexpected benzene oxidation in collisions with superoxide anions” Scientific Reports, vol. 11, (2024).[Bibtex]
@article{ author = {Carlos Guerra, Sarvesh Kumar, Fernando Aguilar-Galindo, Sergio DÃaz-Tendero, Ana Isabel Lozano, Mónica Mendes, Paulo Limão-Vieira, Gustavo Garcia}, title = {Unexpected benzene oxidation in collisions with superoxide anions}, journal = {Scientific Reports}, volume = {11}, number = {}, abstract = {Superoxide anions colliding with benzene molecules at impact energies from 200 to 900 eV are reported for the first time to form massive complexes. With the aid of quantum chemistry calculations, we propose a mechanism in which a sudden double ionization of benzene and the subsequent electrostatic attraction between the dication and the anion form a stable covalently bonded C 6 H 6 O 2 ⁺ molecule, that evolves towards the formation of benzene-diol conformers. These findings lend support to a model presenting a new high energy anion-driven chemistry as an alternative way to form complex molecules.}, year = {2024}, type= {article}, }
- Vladimir A. Srećković, Ljubinko M. Ignjatović and Milan S. Dimitrijević, “Photodestruction of Diatomic Molecular Ions: Laboratory and Astrophysical Application” Molecules, vol. 26, 151 (2020).[Bibtex]
@article{ author = {Vladimir A. Srećković, Ljubinko M. Ignjatović and Milan S. Dimitrijević}, title = {Photodestruction of Diatomic Molecular Ions: Laboratory and Astrophysical Application}, journal = {Molecules}, volume = {26}, number = {151}, abstract = {In this work, the processes of photodissociation of some diatomic molecular ions are investigated. The partial photodissociation cross-sections for the individual rovibrational states of the diatomic molecular ions, which involves alkali metals, as well as corresponding data on molecular species and molecular state characterizations, are calculated. Also, the average cross-section and the corresponding spectral absorption rate coefficients for those small molecules are presented in tabulated form as a function of wavelengths and temperatures. The presented results can be of interest for laboratory plasmas as well as for the research of chemistry of different stellar objects with various astrophysical plasmas.}, year = {2020}, type= {Article}, }
- Ewa Erdmann, Néstor F. Aguirre, Suvasthika Indrajith, Jacopo Chiarinelli, Alicja Domaracka, Patrick Rousseau, Bernd A. Huber, Paola Bolognesi, Robert Richter, Lorenzo Avaldi, Sergio Díaz-Tendero, Manuel Alcamí and Marta Åabuda*, “A general approach to study molecular fragmentation and energy redistribution after an ionizing event” Physical Chemistry Chemical Physics, vol. 23, (2020).[Bibtex]
@article{ author = {Ewa Erdmann, Néstor F. Aguirre, Suvasthika Indrajith, Jacopo Chiarinelli, Alicja Domaracka, Patrick Rousseau, Bernd A. Huber, Paola Bolognesi, Robert Richter, Lorenzo Avaldi, Sergio Díaz-Tendero, Manuel Alcamí and Marta Åabuda*}, title = {A general approach to study molecular fragmentation and energy redistribution after an ionizing event}, journal = {Physical Chemistry Chemical Physics}, volume = {23}, number = {}, abstract = {We propose to combine quantum chemical calculations, statistical mechanical methods, and photoionization and particle collision experiments to unravel the redistribution of internal energy of the furan cation and its dissociation pathways. This approach successfully reproduces the relative intensity of the different fragments as a function of the internal energy of the system in photoelectron–photoion coincidence experiments and the different mass spectra obtained when ions ranging from Ar+ to Xe25+ or electrons are used in collision experiments. It provides deep insights into the redistribution of the internal energy in the ionized molecule and its influence on the dissociation pathways and resulting charged fragments. The present pilot study demonstrates the efficiency of a statistical exchange of excitation energy among various degrees of freedom of the molecule and proves that the proposed approach is mature to be extended to more complex systems.}, year = {2020}, type= {Article}, }
- Gao-Lei Hou, Endre Faragó, Dániel Buzsáki, László Nyulászi, Tibor Höltzl, Ewald Janssens, “Observation of the Reaction Intermediates of Methanol Dehydrogenation by Cationic Vanadium Clusters” Angewandte Chemie International Edition , vol. 60, 9 (2020).[Bibtex]
@article{ author = {Gao-Lei Hou, Endre Faragó, Dániel Buzsáki, László Nyulászi, Tibor Höltzl, Ewald Janssens}, title = {Observation of the Reaction Intermediates of Methanol Dehydrogenation by Cationic Vanadium Clusters}, journal = {Angewandte Chemie International Edition }, volume = {60}, number = {9}, abstract = {A mass spectrometric study of the reactions of vanadium cationic clusters with methanol in a low‐pressure collision cell is reported. For comparison, the reaction of methanol with cobalt cationic clusters was studied. For vanadium, the main reaction products are fully dehydrogenated species, and partial dehydrogenation and non‐dehydrogenation species are observed as minors, for which the relative intensities increase with cluster size and also at low cluster source temperature cooled by liquid nitrogen; no dehydrogenation products were observed for cobalt clusters. Quantum chemical calculations explored the reaction pathways and revealed that the fully dehydrogenation products of the reaction between Vn+ and methanol are Vn(C)(O)+, in which C and O are separated owing to the high oxophilicity of vanadium. The partial dehydrogenation and non‐dehydrogenation species were verified to be reaction intermediates along the reaction pathway, and their most probable structures were proposed.}, year = {2020}, type= {Article}, }
- Nissrin Alharzali, Raúl Rodríguez-Segundoac and Rita Prosmiti, “Modelling interactions of cationic dimers in He droplets: microsolvation trends in HenK2+ clusters” Physical Chemistry Chemical Physics, vol. 23, 13 (2020).[Bibtex]
@article{ author = {Nissrin Alharzali, Raúl Rodríguez-Segundoac and Rita Prosmiti}, title = {Modelling interactions of cationic dimers in He droplets: microsolvation trends in HenK2+ clusters}, journal = {Physical Chemistry Chemical Physics}, volume = {23}, number = {13}, abstract = {We report the results of a detailed theoretical investigation of small K2+-doped He clusters. The structural characteristics and stabilities of such cations are determined from ab initio electronic structure calculations at the MRCI+Q level of theory. The underlying interactions show a multireference character and such effects are analyzed. The interaction potentials are constructed employing an interpolation technique within the inverse problem theory method{,} while the nuclear quantum effects are computed for the trimers{,} their spatial arrangements are discussed{,} and information was extracted on the orientational anisotropy of the forces. We found that energetically the most stable conformer corresponds to linear arrangements that are taking place under large amplitude vibrations{,} with high zero-point energy. We have further looked into the behavior of higher-order species with various He atoms surrounding the cationic dopant. By using a sum of potentials approach and an evolutionary programming method{,} we analyzed the structural stability of clusters with up to six He atoms in comparison with interactions energies obtained from MRCI+Q quantum chemistry computations. Structures containing Hen motifs that characterize pure rare gas clusters{,} appear for the larger K2+-doped He clusters{,} showing selective growth during the microsolvation process of the alkali-dimer cation surrounded by He atoms. Such results indicate the existence of local solvation microstructures in these aggregates{,} where the cationic impurity could get trapped for a short time{,} contributing to the slow ionic mobility observed experimentally in ultra-cold He-droplets.}, year = {2020}, type= {Article}, }
- Mark H. Stockett, James N. Bull, Jack T. Buntine, Eduardo Carrascosa, MingChao Ji, Naoko Kono, Henning T. Schmidt, and Henning Zettergren, “Unimolecular fragmentation and radiative cooling of isolated PAH ions: A quantitative study” J. Chem. Phys., vol. 153, 154303 (2020).[Bibtex]
@article{ author = {Mark H. Stockett, James N. Bull, Jack T. Buntine, Eduardo Carrascosa, MingChao Ji, Naoko Kono, Henning T. Schmidt, and Henning Zettergren}, title = {Unimolecular fragmentation and radiative cooling of isolated PAH ions: A quantitative study}, journal = {J. Chem. Phys.}, volume = {153}, number = {154303}, abstract = {}, year = {2020}, type= {Article}, }
- Giuseppe Mattioli, Lorenzo Avaldi, Paola Bolognesi, John D. Bozek, Mattea C. Castrovilli, Jacopo Chiarinelli, Alicja Domaracka, Suvasthika Indrajith, Sylvain Maclot, Aleksandar R. Milosavljević, Chiara Nicolafrancescobc and Patrick Rousseau, “Unravelling molecular interactions in uracil clusters by XPS measurements assisted by ab initio and tight-binding simulations” Scientific Reports, vol. 10, 13081 (2020).[Bibtex]
@article{ author = {Giuseppe Mattioli, Lorenzo Avaldi, Paola Bolognesi, John D. Bozek, Mattea C. Castrovilli, Jacopo Chiarinelli, Alicja Domaracka, Suvasthika Indrajith, Sylvain Maclot, Aleksandar R. Milosavljević, Chiara Nicolafrancescobc and Patrick Rousseau}, title = {Unravelling molecular interactions in uracil clusters by XPS measurements assisted by ab initio and tight-binding simulations}, journal = {Scientific Reports}, volume = {10}, number = {13081}, abstract = {}, year = {2020}, type= {Article}, }
- P. Rousseau, D.G. Piekarski, M. Capron, A. Domaracka, L. Adoui, F. MartÃn, M. AlcamÃ, S. DÃaz-Tendero and B.A. Huber, “Polypeptide formation in clusters of β-alanine amino acids by single ion impact” Nature Communications, vol. 11, 3818 (2020).[Bibtex]
@article{ author = {P. Rousseau, D.G. Piekarski, M. Capron, A. Domaracka, L. Adoui, F. MartÃn, M. AlcamÃ, S. DÃaz-Tendero and B.A. Huber}, title = {Polypeptide formation in clusters of β-alanine amino acids by single ion impact}, journal = {Nature Communications}, volume = {11}, number = {3818}, abstract = {The formation of peptide bonds by energetic processing of amino acids is an important step towards the formation of biologically relevant molecules. As amino acids are present in space, scenarios have been developed to identify the roots of life on Earth, either by processes occurring in outer space or on Earth itself. We study the formation of peptide bonds in single collisions of low-energy He2+ ions (α-particles) with loosely bound clusters of β-alanine molecules at impact energies typical for solar wind. Experimental fragmentation mass spectra produced by collisions are compared with results of molecular dynamics simulations and an exhaustive exploration of potential energy surfaces. We show that peptide bonds are efficiently formed by water molecule emission, leading to the formation of up to tetrapeptide. The present results show that a plausible route to polypeptides formation in space is the collision of energetic ions with small clusters of amino acids.}, year = {2020}, type= {Article}, }
- Aleš Vítek*, Daniel J. Arismendi-Arrieta*, Martina Šarmanová, René Kalus, and Rita Prosmiti*, “Finite Systems under Pressure: Assessing Volume Definition Models from Parallel-Tempering Monte Carlo Simulations” The Journal of Physical Chemistry A, vol. 124, 20 (2020).[Bibtex]
@article{ author = {Aleš Vítek*, Daniel J. Arismendi-Arrieta*, Martina Šarmanová, René Kalus, and Rita Prosmiti*}, title = {Finite Systems under Pressure: Assessing Volume Definition Models from Parallel-Tempering Monte Carlo Simulations}, journal = {The Journal of Physical Chemistry A}, volume = {124}, number = {20}, abstract = {}, year = {2020}, type= {Article}, }
- Paola Bolognesi, Antti Kettunen, Patrick O'Keeffe1, Robert Richter, Antonella Cartoni, Anna Rita Casavola1, Mattea C Castrovilli1, Sanja Tosic, Bratislav P Marinkovic, Lorenzo Avaldi, “Inner shell photofragmentation of 2Cl-pyrimidine studied by mass spectrometry and electron-ion coincidence experiments” Journal of Physics B: Atomic, Molecular and Optical Physics, vol. 53, 24 (2024).[Bibtex]
@article{ author = {Paola Bolognesi, Antti Kettunen, Patrick O'Keeffe1, Robert Richter, Antonella Cartoni, Anna Rita Casavola1, Mattea C Castrovilli1, Sanja Tosic, Bratislav P Marinkovic, Lorenzo Avaldi}, title = {Inner shell photofragmentation of 2Cl-pyrimidine studied by mass spectrometry and electron-ion coincidence experiments}, journal = {Journal of Physics B: Atomic, Molecular and Optical Physics}, volume = {53}, number = {24}, abstract = {Photoelectron spectroscopy, mass spectrometry and electron–ion coincidence experiments combined with tunable synchrotron radiation have been used to study the decay and fragmentation of 2Cl-pyrimidine after Cl(2p), C(1s) and N(1s) excitations. The goal is to investigate how the state- and site-selected excitation and the chemical environment affect the fragmentation paths of the molecule and to make a comparison with fragmentation induced by direct valence ionization. It has been found that the site-selective inner shell excitation affects the branching ratio of the fragments, while the particular fragmentation channels of the cation are determined by the final state populated in the resonant decay of the core excited states. Effects of nuclear motion in the core excited states and the possible ultrafast molecular dissociation following the Cl(2p → σ*) core excitation are discussed.}, year = {2024}, type= {article}, }
Other publications acknowledging the Action:
- M. Jarraya, A. Bellili, L. Barreau, D. Cubaynes, G. A. Garcia, L. Poisson, M. Hochlaf, “Probing the dynamics of the photo-induced decarboxylation of neutral and ionic pyruvic acid” Farraday Discussions, vol. 238, 266 (2022).[Bibtex]
@article{ author = {M. Jarraya, A. Bellili, L. Barreau, D. Cubaynes, G. A. Garcia, L. Poisson, M. Hochlaf}, title = {Probing the dynamics of the photo-induced decarboxylation of neutral and ionic pyruvic acid}, journal = {Farraday Discussions}, volume = {238}, number = {266}, abstract = {}, year = {2022}, type= {paper2}, }
- Ana I. Lozano, Adrián GarcÃa-Abenza, Francisco Blanco Ramos, Mahmudul Hasan, Daniel S. Slaughter, Thorsten Weber, Robert P. McEachran, Ronald D. White, Michael J. Brunger, Paulo Limao-Vieira, ̃ and Gustavo GarcÃa Gómez-Tejedor, “Electron and Positron Scattering Cross Sections from CO2: A Comparative Study over a Broad Energy Range (0.1–5000 eV)” The Journal of Physical Chemistry A, vol. 126 (36), 6032 (2022).[Bibtex]
@article{ author = {Ana I. Lozano, Adrián GarcÃa-Abenza, Francisco Blanco Ramos, Mahmudul Hasan, Daniel S. Slaughter, Thorsten Weber, Robert P. McEachran, Ronald D. White, Michael J. Brunger, Paulo Limao-Vieira, ̃ and Gustavo GarcÃa Gómez-Tejedor}, title = {Electron and Positron Scattering Cross Sections from CO2: A Comparative Study over a Broad Energy Range (0.1–5000 eV)}, journal = {The Journal of Physical Chemistry A}, volume = {126 (36)}, number = {6032}, abstract = {}, year = {2022}, type= {paper2}, }
- A. Souza-Barbosa, M.Mendes, N.C.Jones, S.V.Hoffmann, M.H.F.Bettega, M.J.Brungerd and P.Limão-Vieira, “Low-lying electronic states of ethanol investigated by theoretical and synchrotron radiation methods” Journal of Quantitative Spectroscopy and Radiative Transfer, vol. 285, 108170 (2022).[Bibtex]
@article{ author = {A. Souza-Barbosa, M.Mendes, N.C.Jones, S.V.Hoffmann, M.H.F.Bettega, M.J.Brungerd and P.Limão-Vieira}, title = {Low-lying electronic states of ethanol investigated by theoretical and synchrotron radiation methods}, journal = {Journal of Quantitative Spectroscopy and Radiative Transfer}, volume = {285}, number = {108170}, abstract = {}, year = {2022}, type= {paper2}, }
- Christine Lochmann , Thomas F. M. Luxford, Samanta Makurat, Andriy Pysanenko, Jaroslav KociÅ¡ek , Janusz Rak and Stephan Denifl , “Low-Energy Electron Induced Reactions in Metronidazole at Different Solvation Conditions” Pharmaceuticals , vol. 15 (6), 701 (2022).[Bibtex]
@article{ author = {Christine Lochmann , Thomas F. M. Luxford, Samanta Makurat, Andriy Pysanenko, Jaroslav Kocišek , Janusz Rak and Stephan Denifl }, title = {Low-Energy Electron Induced Reactions in Metronidazole at Different Solvation Conditions}, journal = {Pharmaceuticals }, volume = {15 (6)}, number = {701}, abstract = {}, year = {2022}, type= {paper2}, }
- Sandra D. Wiersma, Alessandra Candian, Joost M. Bakker, Annemieke Petrignani, “Gas-phase spectroscopy of photostable PAH ions from the mid- to far-infrared” Monthly Notices of the Royal Astronomical Society, vol. 516 (4), 5216 (2022).[Bibtex]
@article{ author = {Sandra D. Wiersma, Alessandra Candian, Joost M. Bakker, Annemieke Petrignani}, title = {Gas-phase spectroscopy of photostable PAH ions from the mid- to far-infrared}, journal = {Monthly Notices of the Royal Astronomical Society}, volume = {516 (4)}, number = {5216}, abstract = {}, year = {2022}, type= {paper2}, }
- Xin Wang, Sivasudhan Rathnachalam, Vicente Zamudio-Bayer, Klaas Bijlsma, Wen Li, Ronnie Hoekstra, Markus Kubin, Martin Timm, Bernd von Issendorff, J. Tobias Lau, Shirin Faraji and Thomas Schlathölter , “Intramolecular hydrogen transfer in DNA induced by site-selective resonant core excitation” Physical Chemistry Chemical Physics, vol. 24, 7815 (2022).[Bibtex]
@article{ author = {Xin Wang, Sivasudhan Rathnachalam, Vicente Zamudio-Bayer, Klaas Bijlsma, Wen Li, Ronnie Hoekstra, Markus Kubin, Martin Timm, Bernd von Issendorff, J. Tobias Lau, Shirin Faraji and Thomas Schlathölter }, title = {Intramolecular hydrogen transfer in DNA induced by site-selective resonant core excitation}, journal = {Physical Chemistry Chemical Physics}, volume = {24}, number = {7815}, abstract = {}, year = {2022}, type= {paper2}, }
- Sarvesh Kumar, Islem Ben Chouikha, Boutheïna Kerkeni, Gustavo GarcÃa and Paulo Limão-Vieira, “Bound Electron Enhanced Radiosensitisation of Nimorazole upon Charge Transfer” Molecules, vol. 27 (13), 4134 (2022).[Bibtex]
@article{ author = {Sarvesh Kumar, Islem Ben Chouikha, Boutheïna Kerkeni, Gustavo GarcÃa and Paulo Limão-Vieira}, title = {Bound Electron Enhanced Radiosensitisation of Nimorazole upon Charge Transfer}, journal = {Molecules}, volume = {27 (13)}, number = {4134}, abstract = {}, year = {2022}, type= {paper2}, }
- Boxing Zhu, James N. Bull, MingChao Ji, Henning Zettergren and Mark H. Stockett, “Radiative cooling rates of substituted PAH ions” The Journal of Chemical Physics, vol. 157, 044303 (2022).[Bibtex]
@article{ author = {Boxing Zhu, James N. Bull, MingChao Ji, Henning Zettergren and Mark H. Stockett}, title = {Radiative cooling rates of substituted PAH ions}, journal = {The Journal of Chemical Physics}, volume = {157}, number = {044303}, abstract = {}, year = {2022}, type= {paper2}, }
- Emanuele Marsili, Antonio Prlj and Basile F. E. Curchod, “A Theoretical Perspective on the Actinic Photochemistry of 2‑Hydroperoxypropanal” The Journal of Physical Chemistry A , vol. 126 (32), 5420 (2022).[Bibtex]
@article{ author = {Emanuele Marsili, Antonio Prlj and Basile F. E. Curchod}, title = {A Theoretical Perspective on the Actinic Photochemistry of 2‑Hydroperoxypropanal}, journal = {The Journal of Physical Chemistry A }, volume = {126 (32)}, number = {5420}, abstract = {}, year = {2022}, type= {paper2}, }
- Raul Rodriguez-Segundo, Alfonso Gijon and Rita Prosmiti, “Quantum molecular simulations of micro-hydrated halogen anions” Physical Chemistry Chemical Physics, vol. 24, 14964 (2022).[Bibtex]
@article{ author = {Raul Rodriguez-Segundo, Alfonso Gijon and Rita Prosmiti}, title = {Quantum molecular simulations of micro-hydrated halogen anions}, journal = {Physical Chemistry Chemical Physics}, volume = {24}, number = {14964}, abstract = {}, year = {2022}, type= {paper2}, }
- Raquel Yanes-Rodriguez Adriana Cabrera-Ramirez and Rita Prosmiti, “Delving into guest-free and He-filled sI and sII clathrate hydrates: a first-principles computational study” Physical Chemistry Chemical Physics, vol. 24, 13119 (2022).[Bibtex]
@article{ author = {Raquel Yanes-Rodriguez Adriana Cabrera-Ramirez and Rita Prosmiti}, title = {Delving into guest-free and He-filled sI and sII clathrate hydrates: a first-principles computational study}, journal = {Physical Chemistry Chemical Physics}, volume = {24}, number = {13119}, abstract = {}, year = {2022}, type= {paper2}, }
- Orlando Carrillo-Bohórquez, Ãlvaro Valdés and Rita Prosmiti, “Unraveling the Origin of Symmetry Breaking in H2O@C60 Endofullerene Through Quantum Computations” ChemPhysChem, vol. 23 (9), e202200034 (2022).[Bibtex]
@article{ author = {Orlando Carrillo-Bohórquez, Ãlvaro Valdés and Rita Prosmiti}, title = {Unraveling the Origin of Symmetry Breaking in H2O@C60 Endofullerene Through Quantum Computations}, journal = {ChemPhysChem}, volume = {23 (9)}, number = {e202200034}, abstract = {}, year = {2022}, type= {paper2}, }
- Connor J. Clarke , Jemma A. Gibbard , Lewis Hutton, Jan R. R. Verlet and Basile F. E. Curchod , “Photochemistry of the pyruvate anion produces CO2, CO, CH3–, CH3, and a low energy electron” Nature Communications, vol. 13, 937 (2022).[Bibtex]
@article{ author = {Connor J. Clarke , Jemma A. Gibbard , Lewis Hutton, Jan R. R. Verlet and Basile F. E. Curchod }, title = {Photochemistry of the pyruvate anion produces CO2, CO, CH3–, CH3, and a low energy electron}, journal = {Nature Communications}, volume = {13}, number = {937}, abstract = {}, year = {2022}, type= {paper2}, }
- Adriana Cabrera-RamÃrez and Rita Prosmiti, “Modeling of Structure H Carbon Dioxide Clathrate Hydrates: Guest−Lattice Energies, Crystal Structure, and Pressure Dependencies” The Journal of Physical Chemistry C, vol. 126, 14832 (2022).[Bibtex]
@article{ author = {Adriana Cabrera-RamÃrez and Rita Prosmiti}, title = {Modeling of Structure H Carbon Dioxide Clathrate Hydrates: Guest−Lattice Energies, Crystal Structure, and Pressure Dependencies}, journal = {The Journal of Physical Chemistry C}, volume = {126}, number = {14832}, abstract = {}, year = {2022}, type= {paper2}, }
- Paola Bolognesi and Lorenzo Avaldi, “Photoelectron–photoion(s) coincidence studies of molecules of biological interest” Physical Chemistry Chemical Physics, vol. 24, 22356 (2022).[Bibtex]
@article{ author = {Paola Bolognesi and Lorenzo Avaldi}, title = {Photoelectron–photoion(s) coincidence studies of molecules of biological interest}, journal = {Physical Chemistry Chemical Physics}, volume = {24}, number = {22356}, abstract = {}, year = {2022}, type= {paper2}, }
- Daniela V. Coelho and João Brandão and César Mogo, “Internal energy and temperature of a carbon nanotube” Fullerenes, Nanotubes and Carbon Nanostructures, vol. 0, 1 (2022).[Bibtex]
@article{ author = {Daniela V. Coelho and João Brandão and César Mogo}, title = {Internal energy and temperature of a carbon nanotube}, journal = {Fullerenes, Nanotubes and Carbon Nanostructures}, volume = {0}, number = {1}, abstract = {}, year = {2022}, type= {paper2}, }
- Laura Carlini, Jacopo Chiarinelli, Giuseppe Mattioli, Mattea Carmen Castrovilli, Veronica Valentini, Adriana De Stefanis, Elvira Maria Bauer, Paola Bolognesi, and Lorenzo Avaldi, “Insights into the Thermally Activated Cyclization Mechanism in a Linear Phenylalanine-Alanine Dipeptide” The Journal of Physical Chemistry B, vol. 126 (16), 2968 (2022).[Bibtex]
@article{ author = {Laura Carlini, Jacopo Chiarinelli, Giuseppe Mattioli, Mattea Carmen Castrovilli, Veronica Valentini, Adriana De Stefanis, Elvira Maria Bauer, Paola Bolognesi, and Lorenzo Avaldi}, title = {Insights into the Thermally Activated Cyclization Mechanism in a Linear Phenylalanine-Alanine Dipeptide}, journal = {The Journal of Physical Chemistry B}, volume = {126 (16)}, number = {2968}, abstract = {}, year = {2022}, type= {paper2}, }
- Mauro Satta, Daniele Catone, Mattea Carmen Castrovilli, Paola Bolognesi, Lorenzo Avaldi, Nicola Zema, and Antonella Cartoni, “Ion Chemistry of Carbon Dioxide in Nonthermal Reaction with Molecular Hydrogen” The Journal of Physical Chemistry A, vol. 126 (22), 3463 (2022).[Bibtex]
@article{ author = {Mauro Satta, Daniele Catone, Mattea Carmen Castrovilli, Paola Bolognesi, Lorenzo Avaldi, Nicola Zema, and Antonella Cartoni}, title = {Ion Chemistry of Carbon Dioxide in Nonthermal Reaction with Molecular Hydrogen}, journal = {The Journal of Physical Chemistry A}, volume = {126 (22)}, number = {3463}, abstract = {}, year = {2022}, type= {paper2}, }
- A. Albinati, M. Grellier, J. Ollivier, and P.A. Georgiev, “On the energetics of binding and hydride exchange in the RuH2(H2)2[P(C5H9)3)]2 complex as revealed by inelastic neutron scattering and DFT studies” New Journal of Chemistry, vol. 46, 14649 (2022).[Bibtex]
@article{ author = {A. Albinati, M. Grellier, J. Ollivier, and P.A. Georgiev}, title = {On the energetics of binding and hydride exchange in the RuH2(H2)2[P(C5H9)3)]2 complex as revealed by inelastic neutron scattering and DFT studies}, journal = {New Journal of Chemistry}, volume = {46}, number = {14649}, abstract = {}, year = {2022}, type= {paper2}, }
- Michael Gatchell and Henning Zettergren, “Open questions on the interaction dynamics of molecules and clusters in the gas phase” Communications Chemistry, vol. 5, 28 (2022).[Bibtex]
@article{ author = {Michael Gatchell and Henning Zettergren}, title = {Open questions on the interaction dynamics of molecules and clusters in the gas phase}, journal = {Communications Chemistry}, volume = {5}, number = {28}, abstract = {}, year = {2022}, type= {paper2}, }
- Mark H Stockett, James N Bull, Henning T Schmidt and Henning Zettergren, “Statistical vibrational autodetachment and radiative cooling rates of para-benzoquinone” Physical Chemistry Chemical Physics, vol. 24, 12002 (2022).[Bibtex]
@article{ author = {Mark H Stockett, James N Bull, Henning T Schmidt and Henning Zettergren}, title = {Statistical vibrational autodetachment and radiative cooling rates of para-benzoquinone}, journal = {Physical Chemistry Chemical Physics}, volume = {24}, number = {12002}, abstract = {}, year = {2022}, type= {paper2}, }
- Alexandra J. Feinberg et al., “X-ray diffractive imaging of highly ionized helium nanodroplets” Phys. Rev. Research , vol. 4, L022063 (2022).[Bibtex]
@article{ author = {Alexandra J. Feinberg et al.}, title = {X-ray diffractive imaging of highly ionized helium nanodroplets}, journal = {Phys. Rev. Research }, volume = {4}, number = {L022063}, abstract = {}, year = {2022}, type= {paper2}, }
- Betül ErmiÅŸ, Emel Ekinci, and UÄŸur Bozkaya*, “State-Of-The-Art Computations of Vertical Electron Affinities with the Extended Koopmans' Theorem Integrated with the CCSD(T) Method” Journal of Chemical Theory and Computation, vol. 17, 12 (2021).[Bibtex]
@article{ author = {Betül ErmiÅŸ, Emel Ekinci, and UÄŸur Bozkaya*}, title = {State-Of-The-Art Computations of Vertical Electron Affinities with the Extended Koopmans' Theorem Integrated with the CCSD(T) Method}, journal = {Journal of Chemical Theory and Computation}, volume = {17}, number = {12}, abstract = {}, year = {2021}, type= {Article}, }
- Orlando Carrillo-Bohórquez, Álvaro Valdés*, and Rita Prosmiti*, “Encapsulation of a Water Molecule inside C60 Fullerene: The Impact of Confinement on Quantum Features” Journal of Chemical Theory and Computation, vol. 17, 9 (2021).[Bibtex]
@article{ author = {Orlando Carrillo-Bohórquez, Álvaro Valdés*, and Rita Prosmiti*}, title = {Encapsulation of a Water Molecule inside C60 Fullerene: The Impact of Confinement on Quantum Features}, journal = {Journal of Chemical Theory and Computation}, volume = {17}, number = {9}, abstract = {}, year = {2021}, type= {Article}, }
- Emanuele Marsili, Antonio Prlj, Basile F. E. Curchod, “Caveat when using ADC(2) for studying the photochemistry of carbonyl-containing molecules” Physical Chemistry and Chemical Physics, vol. 23, (2021).[Bibtex]
@article{ author = {Emanuele Marsili, Antonio Prlj, Basile F. E. Curchod}, title = {Caveat when using ADC(2) for studying the photochemistry of carbonyl-containing molecules}, journal = {Physical Chemistry and Chemical Physics}, volume = {23}, number = {}, abstract = {Several electronic-structure methods are available to study the photochemistry and photophysics of organic molecules. Among them, ADC(2) stands as a sweet spot between computational efficiency and accuracy. As a result, ADC(2) has recently seen its number of applications booming, in particular to unravel the deactivation pathways and photodynamics of organic molecules. Despite this growing success, we demonstrate here that care has to be taken when studying the nonradiative pathways of carbonyl- containing molecules, as ADC(2) appears to suffer from a systematic flaw.}, year = {2021}, type= {Communication}, }
- Yorick Lassmann, Basile F. E. Curchod, “AIMSWISS – Ab initio multiple spawning with informed stochastic selections” Journal of Chemical Physics, vol. 154, 211106 (2021).[Bibtex]
@article{ author = {Yorick Lassmann, Basile F. E. Curchod}, title = {AIMSWISS – Ab initio multiple spawning with informed stochastic selections}, journal = {Journal of Chemical Physics}, volume = {154}, number = {211106}, abstract = {Ab initio multiple spawning (AIMS) offers a reliable strategy to describe the excited-state dynamics and nonadiabatic processes of molecular systems. AIMS represents nuclear wavefunctions as linear combinations of traveling, coupled Gaussians called trajectory basis functions (TBFs) and uses a spawning algorithm to increase as needed the size of this basis set during nonadiabatic transitions. While the success of AIMS resides in this spawning algorithm, the dramatic increase in TBFs generated by multiple crossings between electronic states can rapidly lead to intractable dynamics. In this Communication, we introduce a new flavor of AIMS, coined ab initio multiple spawning with informed stochastic selections (AIMSWISS), which proposes a parameter-free strategy to beat the growing number of TBFs in an AIMS dynamics while preserving its accurate description of nonadiabatic transitions. The performance of AIMSWISS is validated against the photodynamics of ethylene, cyclopropanone, and fulvene. This technique, built upon the recently developed stochastic-selection AIMS, is intended to serve as a computationally affordable starting point for multiple spawning simulations.}, year = {2021}, type= {Communication}, }
- Daniele Catone, Mauro Satta, Mattea Carmen Castrovilli, Paola Bolognesi, Lorenzo Avaldi, Antonella Cartoni, “Photoionization of methanol: a molecular source for the prebiotic chemistry” Chemical Physics Letters, vol. 771, 138467 (2021).[Bibtex]
@article{ author = {Daniele Catone, Mauro Satta, Mattea Carmen Castrovilli, Paola Bolognesi, Lorenzo Avaldi, Antonella Cartoni}, title = {Photoionization of methanol: a molecular source for the prebiotic chemistry}, journal = {Chemical Physics Letters}, volume = {771}, number = {138467}, abstract = {}, year = {2021}, type= {Article}, }
- Adriana Cabrera-Ramírez, Raquel Yanes-Rodríguez, and Rita Prosmiti, “Computational density-functional approaches on finite-size and guest-lattice effects in CO2@sII clathrate hydrate” The Journal of Chemical Physics, vol. 154, 4 (2021).[Bibtex]
@article{ author = {Adriana Cabrera-Ramírez, Raquel Yanes-Rodríguez, and Rita Prosmiti}, title = {Computational density-functional approaches on finite-size and guest-lattice effects in CO2@sII clathrate hydrate}, journal = {The Journal of Chemical Physics}, volume = {154}, number = {4}, abstract = {}, year = {2021}, type= {Article}, }
- Jelena Tamuliene, Liudmila Romanova, Vasyl Vukstich, Vasyl Rizak & Alexander Snegursky , “Fragmentation of threonine under low-energy electron impact” The European Physical Journal D, vol. 75, 31 (2021).[Bibtex]
@article{ author = {Jelena Tamuliene, Liudmila Romanova, Vasyl Vukstich, Vasyl Rizak & Alexander Snegursky }, title = {Fragmentation of threonine under low-energy electron impact}, journal = {The European Physical Journal D}, volume = {75}, number = {31}, abstract = {}, year = {2021}, type= {Article}, }
- Bull, JN; Anstoter, CS; Stockett, MH; Clarke, CJ; Gibbard, JA; Bieske, EJ; Verlet, JRR, “Nonadiabatic Dynamics between Valence, Nonvalence, and Continuum Electronic States in a Heteropolycyclic Aromatic Hydrocarbon” Journal of Physical Chemistry Letters, vol. 12, 49 (2021).[Bibtex]
@article{ author = {Bull, JN; Anstoter, CS; Stockett, MH; Clarke, CJ; Gibbard, JA; Bieske, EJ; Verlet, JRR}, title = {Nonadiabatic Dynamics between Valence, Nonvalence, and Continuum Electronic States in a Heteropolycyclic Aromatic Hydrocarbon}, journal = {Journal of Physical Chemistry Letters}, volume = {12}, number = {49}, abstract = {}, year = {2021}, type= {}, }
- Wasowicz, TJ; Pranszke, B, “Optical Spectroscopic Studies of Tetrahydrofuran Fragmentation Induced by Collisions with Dihydrogen Cations” Acta Physica Polonica A, vol. 140, 3 (2021).[Bibtex]
@article{ author = {Wasowicz, TJ; Pranszke, B}, title = {Optical Spectroscopic Studies of Tetrahydrofuran Fragmentation Induced by Collisions with Dihydrogen Cations}, journal = {Acta Physica Polonica A}, volume = {140}, number = {3}, abstract = {}, year = {2021}, type= {}, }
- Tamuliene, J; Romanova, L; Vukstich, V; Snegursky, A, “Fragmentation of tyrosine by low-energy electron impact” European Physical Journal D, vol. 75, 9 (2021).[Bibtex]
@article{ author = {Tamuliene, J; Romanova, L; Vukstich, V; Snegursky, A}, title = {Fragmentation of tyrosine by low-energy electron impact}, journal = {European Physical Journal D}, volume = {75}, number = {9}, abstract = {}, year = {2021}, type= {}, }
- Cabrera-Ramirez, A; Arismendi-Arrieta, DJ; Vald?s, A; Prosmiti, R, “Exploring CO2@sI Clathrate Hydrates as CO2 Storage Agents by Computational Density Functional Approaches” ChemPhysChem, vol. 22, 4 (2021).[Bibtex]
@article{ author = {Cabrera-Ramirez, A; Arismendi-Arrieta, DJ; Vald?s, A; Prosmiti, R}, title = {Exploring CO2@sI Clathrate Hydrates as CO2 Storage Agents by Computational Density Functional Approaches}, journal = {ChemPhysChem}, volume = {22}, number = {4}, abstract = {}, year = {2021}, type= {}, }
- Yanes-Rodriguez, R; Prosmiti, R, “Assessment of DFT approaches in noble gas clathrate-like clusters: stability and thermodynamics” Physical Chemistry Chemical Physics, vol. 24, 3 (2021).[Bibtex]
@article{ author = {Yanes-Rodriguez, R; Prosmiti, R}, title = {Assessment of DFT approaches in noble gas clathrate-like clusters: stability and thermodynamics}, journal = {Physical Chemistry Chemical Physics}, volume = {24}, number = {3}, abstract = {}, year = {2021}, type= {}, }
- Prlj, A; Marsili, E; Hutton, L; Hollas, D; Shchepanovska, D; Glowacki, DR; Slavicek, P; Curchod, BFE, “Calculating Photoabsorption Cross-Sections for Atmospheric Volatile Organic Compounds” ACS Earth and Space Chemistry, vol. 6, 1 (2021).[Bibtex]
@article{ author = {Prlj, A; Marsili, E; Hutton, L; Hollas, D; Shchepanovska, D; Glowacki, DR; Slavicek, P; Curchod, BFE}, title = {Calculating Photoabsorption Cross-Sections for Atmospheric Volatile Organic Compounds}, journal = {ACS Earth and Space Chemistry}, volume = {6}, number = {1}, abstract = {}, year = {2021}, type= {}, }
- Kumar, S; Pereira, PJS; Garcia, G; Limao-Vieira, P, “Cl- kinetic-energy release distributions from chlorobenzene and related molecules in electron transfer experiments” European Physical Journal D, vol. 75, 11 (2021).[Bibtex]
@article{ author = {Kumar, S; Pereira, PJS; Garcia, G; Limao-Vieira, P}, title = {Cl- kinetic-energy release distributions from chlorobenzene and related molecules in electron transfer experiments}, journal = {European Physical Journal D}, volume = {75}, number = {11}, abstract = {}, year = {2021}, type= {}, }
- Wasowicz, TJ, “PHOTON LUMINESCENCE STUDIES OF TETRAHYDROFURAN FOLLOWING TRIHYDROGEN CATIONS IMPACT IN THE 20-1000 EV ENERGY RANGE” Romanian Reports in Physics, vol. 73, 4 (2021).[Bibtex]
@article{ author = {Wasowicz, TJ}, title = {PHOTON LUMINESCENCE STUDIES OF TETRAHYDROFURAN FOLLOWING TRIHYDROGEN CATIONS IMPACT IN THE 20-1000 EV ENERGY RANGE}, journal = {Romanian Reports in Physics}, volume = {73}, number = {4}, abstract = {}, year = {2021}, type= {}, }
- de Oca-Estevez, MJM; Prosmiti, R, “Computational Characterization of Astrophysical Species: The Case of Noble Gas Hydride Cations” Frontiers in Chemistry, vol. 9, (2021).[Bibtex]
@article{ author = {de Oca-Estevez, MJM; Prosmiti, R}, title = {Computational Characterization of Astrophysical Species: The Case of Noble Gas Hydride Cations}, journal = {Frontiers in Chemistry}, volume = {9}, number = {}, abstract = {}, year = {2021}, type= {}, }
- Bolognesi, P; Randazzo, JM; Turri, G; Mathis, J; Penson, C; Ancarani, LU; Avaldi, L, “A combined experimental and theoretical study of photodouble ionization of water at 32 eV excess energy and unequal energy sharing” Journal of Physics B-Atomic Molecular and Optical Physics, vol. 54, 3 (2021).[Bibtex]
@article{ author = {Bolognesi, P; Randazzo, JM; Turri, G; Mathis, J; Penson, C; Ancarani, LU; Avaldi, L}, title = {A combined experimental and theoretical study of photodouble ionization of water at 32 eV excess energy and unequal energy sharing}, journal = {Journal of Physics B-Atomic Molecular and Optical Physics}, volume = {54}, number = {3}, abstract = {}, year = {2021}, type= {}, }
- Satta, M; Casavola, AR; Cartoni, A; Castrovilli, MC; Catone, D; Chiarinelli, J; Borocci, S; Avaldi, L; Bolognesi, P, “Ionization of 2-and 4(5)-Nitroimidazoles Radiosensitizers: a Kinetic Competition Between NO2 and NO Losses” ChemPhysChem, vol. 22, 23 (2021).[Bibtex]
@article{ author = {Satta, M; Casavola, AR; Cartoni, A; Castrovilli, MC; Catone, D; Chiarinelli, J; Borocci, S; Avaldi, L; Bolognesi, P}, title = {Ionization of 2-and 4(5)-Nitroimidazoles Radiosensitizers: a Kinetic Competition Between NO2 and NO Losses}, journal = {ChemPhysChem}, volume = {22}, number = {23}, abstract = {}, year = {2021}, type= {}, }
- Zehra Nur ÖZER, “DIFFERENTIAL CROSS SECTIONS FOR ELASTIC SCATTERING OF ELECTRONS FROM MOLECULAR NITROGEN ” EskiÅŸehir Technical University Journal of Science and Technology A - Applied Sciences and Engineering, vol. 21, 4 (2020).[Bibtex]
@article{ author = {Zehra Nur ÖZER}, title = {DIFFERENTIAL CROSS SECTIONS FOR ELASTIC SCATTERING OF ELECTRONS FROM MOLECULAR NITROGEN }, journal = {EskiÅŸehir Technical University Journal of Science and Technology A - Applied Sciences and Engineering}, volume = {21}, number = {4}, abstract = {}, year = {2020}, type= {Article}, }
- Anna Rita Casavola, Antonella Cartoni*, Mattea Carmen Castrovilli, Stefano Borocci, Paola Bolognesi, Jacopo Chiarinelli, Daniele Catone, and Lorenzo Avaldi, “VUV Photofragmentation of Chloroiodomethane: The Iso-CH2I–Cl and Iso-CH2Cl–I Radical Cation Formation” J. Phys. Chem. A, vol. , (2020).[Bibtex]
@article{ author = {Anna Rita Casavola, Antonella Cartoni*, Mattea Carmen Castrovilli, Stefano Borocci, Paola Bolognesi, Jacopo Chiarinelli, Daniele Catone, and Lorenzo Avaldi}, title = {VUV Photofragmentation of Chloroiodomethane: The Iso-CH2I–Cl and Iso-CH2Cl–I Radical Cation Formation}, journal = {J. Phys. Chem. A}, volume = {}, number = {}, abstract = {Dihalomethanes XCH2Y (X and Y = F, Cl, Br, and I) are a class of compounds involved in several processes leading to the release of halogen atoms, ozone consumption, and aerosol particle formation. Neutral dihalomethanes have been largely studied, but chemical physics properties and processes involving their radical ions, like the pathways of their decomposition, have not been completely investigated. In this work the photodissociation dynamics of the ClCH2I molecule has been explored in the photon energy range 9–21 eV using both VUV rare gas discharge lamps and synchrotron radiation. The experiments show that, among the different fragment ions, CH2I+ and CH2Cl+, which correspond to the Cl- and I-losses, respectively, play a dominant role. The experimental ionization energy of ClCH2I and the appearance energies of the CH2I+ and CH2Cl+ ions are in agreement with the theoretical results obtained at the MP2/CCSD(T) level of theory. Computational investigations have been also performed to study the isomerization of geminal [ClCH2I]•+ into the iso-chloroiodomethane isomers: [CH2I–Cl]•+ and [CH2Cl–I]•+.}, year = {2020}, type= {Article}, }
- Mauro Satta, Antonella Cartoni, Daniele Catone, Mattea Carmen Castrovilli, Paola Bolognesi, Nicola Zema, and Lorenzo Avaldi, “The Reaction of Sulfur Dioxide Radical Cation with Hydrogen and its Relevance in Solar Geoengineering Models” ChemPhysChem, vol. 21, 1-12 (2020).[Bibtex]
@article{ author = {Mauro Satta, Antonella Cartoni, Daniele Catone, Mattea Carmen Castrovilli, Paola Bolognesi, Nicola Zema, and Lorenzo Avaldi}, title = {The Reaction of Sulfur Dioxide Radical Cation with Hydrogen and its Relevance in Solar Geoengineering Models}, journal = {ChemPhysChem}, volume = {21}, number = {1-12}, abstract = {SO2 has been proposed in solar geoengineering as a precursor of H2SO4 aerosol, a cooling agent active in the stratosphere to contrast climate change. Atmospheric ionization sources can ionize SO2 into excited states of urn:x-wiley:14394235:media:cphc202000194:cphc202000194-math-0001 , which quickly reacts with trace gases in the stratosphere. In this work we explore the reaction of urn:x-wiley:14394235:media:cphc202000194:cphc202000194-math-0002 with urn:x-wiley:14394235:media:cphc202000194:cphc202000194-math-0003 excited by tunable synchrotron radiation, leading to urn:x-wiley:14394235:media:cphc202000194:cphc202000194-math-0004 (urn:x-wiley:14394235:media:cphc202000194:cphc202000194-math-0005 ), where H contributes to O3 depletion and OH formation. Density Functional Theory and Variational Transition State Theory have been used to investigate the dynamics of the title barrierless and exothermic reaction. The present results suggest that solar geoengineering models should test the reactivity of urn:x-wiley:14394235:media:cphc202000194:cphc202000194-math-0006 with major trace gases in the stratosphere, such as H2 since this is a relevant channel for the OH formation during the nighttime when there is not OH production by sunlight. OH oxides SO2, triggering the chemical reactions leading to H2SO4 aerosol.}, year = {2020}, type= {Article}, }
Relevant publications from participants in COST MD-GAS Action:
- A. Marciniak, C. Joblin, G. Mulas, V. Rao Mundlapati and A. Bonnamy, “Photodissociation of aliphatic PAH derivatives under relevant astrophysical conditions” A&A, vol. 652, A42 (2021).[Bibtex]
@article{ author = {A. Marciniak, C. Joblin, G. Mulas, V. Rao Mundlapati and A. Bonnamy}, title = {Photodissociation of aliphatic PAH derivatives under relevant astrophysical conditions}, journal = {A&A}, volume = {652}, number = {A42}, abstract = {Context. The interaction of polycyclic aromatic hydrocarbons (PAHs) with vacuum ultraviolet (VUV) photons triggers the emission of the well-known aromatic infrared bands (AIBs), but other mechanisms, such as fragmentation, can be involved in this interaction. Fragmentation leads to selection effects that favor specific sizes and structures. Aims. Our aim is to investigate the impact of aliphatic bonds on the VUV photostability of PAH cations in a cryogenic and collisionless environment with conditions applicable for photodissociation regions (PDRs). Methods. The studied species are derived from pyrene (C16H10) and coronene (C24H12) and contain aliphatic bonds either in the form of methyl or ethyl sidegroups or of superhydrogenation. Their cations are produced by laser desorption ionization and isolated in the cryogenic ion cell of the PIRENEA setup, where they are submitted to VUV photons of 10.5 eV energy over long timescales (~1000 s). The parent and fragment ions are mass-analyzed and their relative intensities are recorded as a function of the irradiation time. The fragmentation cascades are analyzed with a simple kinetics model from which we identify fragmentation pathways and derive fragmentation rates and branching ratios for both the parents and their main fragments. Results. Aliphatic PAH derivatives are found to have a higher fragmentation rate and a higher carbon to hydrogen loss compared to regular PAHs. On the other hand, the fragmentation of PAHs with alkylated sidegroups forms species with peripheral pentagonal cycles, which can be as stable as, or even more stable than, the bare PAH cations. This stability is quantified for the main ions involved in the fragmentation cascades by the comparison of the fragmentation rates with the photoabsorption rates derived from theoretical photoabsorption cross sections. The most stable species for which there is an effective competition of fragmentation with isomerization and radiative cooling are identified, providing clues on the structures favored in PDRs. Conclusions. This work supports a scenario in which the evaporation of nanograins with a mixed aliphatic and aromatic composition followed by VUV photoprocessing results in both the production of the carriers of the 3.4 μm AIB by methyl sidegroups and in an abundant source of small hydrocarbons at the border of PDRs. An additional side effect is the efficient formation of stable PAHs that contain some peripheral pentagonal rings. Our experiments also support the role of isomerization processes in PAH photofragmentation, including the H-migration process, which could lead to an additional contribution to the 3.4 μm AIB.}, year = {2021}, type= {Article}, }
- Fernando Aguilar-Galindo, Andrey G. Borisov, and Sergio Díaz-Tendero*, “Ultrafast Dynamics of Electronic Resonances in Molecules Adsorbed on Metal Surfaces: A Wave Packet Propagation Approach” Journal of Chemical Theory and Computation, vol. 17 (2), (2021).[Bibtex]
@article{ author = {Fernando Aguilar-Galindo, Andrey G. Borisov, and Sergio Díaz-Tendero*}, title = {Ultrafast Dynamics of Electronic Resonances in Molecules Adsorbed on Metal Surfaces: A Wave Packet Propagation Approach}, journal = {Journal of Chemical Theory and Computation}, volume = {17 (2)}, number = {}, abstract = {We present a wave packet propagation-based method to study the electron dynamics in molecular species in the gas phase and adsorbed on metal surfaces. It is a very general method that can be employed to any system where the electron dynamics is dominated by an active electron and the coupling between the discrete and continuum electronic states is of importance. As an example, one can consider resonant molecule–surface electron transfer or molecular photoionization. Our approach is based on a computational strategy allowing incorporating ab initio inputs from quantum chemistry methods, such as density functional theory, Hartree–Fock, and coupled cluster. Thus, the electronic structure of the molecule is fully taken into account. The electron wave function is represented on a three-dimensional grid in spatial coordinates, and its temporal evolution is obtained from the solution of the time-dependent Schrödinger equation. We illustrate our method with an example of the electron dynamics of anionic states localized on organic molecules adsorbed on metal surfaces. In particular, we study resonant charge transfer from the π* orbitals of three vinyl derivatives (acrylamide, acrylonitrile, and acrolein) adsorbed on a Cu(100) surface. Electron transfer between these lowest unoccupied molecular orbitals and the metal surface is extremely fast, leading to a decay of the population of the molecular anion on the femtosecond timescale. We detail how to analyze the time-dependent electronic wave function in order to obtain the relevant information on the system: the energies and lifetimes of the molecule-localized quasistationary states, their resonant wavefunctions, and the population decay channels. In particular, we demonstrate the effect of the electronic structure of the substrate on the energy and momentum distribution of the hot electrons injected into the metal by the decaying molecular resonance.}, year = {2021}, type= {Article}, }
- Dariusz G. Piekarski, Pascal Steinforth, Melania Gómez-MartÃnez, Julia Bamberger, Florian Ostler, Monika Schönhoff, Olga GarcÃa Mancheño, “Insight into the Folding and Cooperative Multiâ€Recognition Mechanism in Supramolecular Anionâ€Binding Catalysis” Chemistry A European Journal, vol. 26, 72 (2020).[Bibtex]
@article{ author = {Dariusz G. Piekarski, Pascal Steinforth, Melania Gómez-MartÃnez, Julia Bamberger, Florian Ostler, Monika Schönhoff, Olga GarcÃa Mancheño}, title = {Insight into the Folding and Cooperative Multiâ€Recognition Mechanism in Supramolecular Anionâ€Binding Catalysis}, journal = {Chemistry A European Journal}, volume = {26}, number = {72}, abstract = {Hâ€bond donor catalysts able to modulate the reactivity of ionic substrates for asymmetric reactions have gained great attention in the past years, leading to the development of cooperative multidentate Hâ€bonding supramolecular structures. However, there is still a lack of understanding of the forces driving the ion recognition and catalytic performance of these systems. Herein, insights into the cooperativity nature, anion binding strength, and folding mechanism of a model chiral triazole catalyst is presented. Our combined experimental and computational study revealed that multiâ€interaction catalysts exhibiting weak binding energies (~3â€4 kcal mol −1 ) can effectively recognize ionic substrates and induce chirality, while strong dependencies on the temperature and solvent were quantified. These results are key for the future design of catalysts with optimal anion binding strength and catalytic activity in target reactions.}, year = {2020}, type= {computational chemistry, MD simulations, , DFT, WF analysis, catalysis}, }
- Johan van der Tol and Ewald Janssens, “Size-dependent velocity distributions and temperatures of metal clusters in a helium carrier gas” Physical Review A, vol. 102, 022806 (2020).[Bibtex]
@article{ author = {Johan van der Tol and Ewald Janssens}, title = {Size-dependent velocity distributions and temperatures of metal clusters in a helium carrier gas}, journal = {Physical Review A}, volume = {102}, number = {022806}, abstract = {Combining a laser vaporization cluster source, a velocity scan system, and a time-of-flight mass spectrometer, we measured velocity distributions of few-atom cobalt clusters ( Co n , n = 6 – 60 ) suspended in a helium carrier gas and expanded into vacuum. The velocity distributions provide information about the cluster size dependence of the translational temperature, flow velocity, and velocity slip with respect to the helium carrier gas. The system of clusters in a carrier gas is found to violate the equipartition theorem. Although the clusters in the expansion do not thermalize with the helium gas, they do experience significant, size-dependent internal cooling. While expanding into vacuum, the clusters collide, at least a couple of hundred times, superelastically with the carrier gas, thereby transferring internal vibrational energy into self-acceleration and increasing the flow velocity of the gas as a whole. It is also demonstrated that the proposed velocity distribution measurements can be used to test whether a source produces thermalized clusters.}, year = {2020}, type= {Article}, }
- Gustav Eklund, Jon Grumer, Stefan Rosén, MingChao Ji, Najeeb Punnakayathil, Anders Källberg, Ansgar Simonsson, Richard D. Thomas, Mark H. Stockett, Peter Reinhed, Patrik Löfgren, Mikael Björkhage, Mikael Blom, Paul S. Barklem, Henrik Cederquist, Henning Zettergren, and Henning T. Schmidt, “Cryogenic merged-ion-beam experiments in DESIREE: Final-state-resolved mutual neutralization of Li+ and D” Physical Review A, vol. 103, 012823 (2020).[Bibtex]
@article{ author = {Gustav Eklund, Jon Grumer, Stefan Rosén, MingChao Ji, Najeeb Punnakayathil, Anders Källberg, Ansgar Simonsson, Richard D. Thomas, Mark H. Stockett, Peter Reinhed, Patrik Löfgren, Mikael Björkhage, Mikael Blom, Paul S. Barklem, Henrik Cederquist, Henning Zettergren, and Henning T. Schmidt}, title = {Cryogenic merged-ion-beam experiments in DESIREE: Final-state-resolved mutual neutralization of Li+ and D}, journal = {Physical Review A}, volume = {103}, number = {012823}, abstract = {We have developed an experimental technique to study charge- and energy-flow processes in sub-eV collisions between oppositely charged, internally cold, ions of atoms, molecules, and clusters. Two ion beams are stored in separate rings of the cryogenic ion-beam storage facility DESIREE, and merged in a common straight section where a set of biased drift tubes is used to control the center-of-mass collision energy locally in fine steps. Here, we present measurements on mutual neutralization between Li+ and D− where a time-sensitive imaging-detector system is used to measure the three-dimensional distance between the neutral Li and D atoms as they reach the detector. This scheme allows for direct measurements of kinetic-energy releases, and here it reveals separate populations of the 3s state and the (3p+3d) states in neutral Li while the D atom is left in its ground state 1s. The branching fraction of the 3s final state is easured to be 57.8±0.7% at a center-of-mass collision energy of 78±13 meV. The technique paves the way for studies of charge-, energy-, and mass-transfer reactions in single collisions involving molecular and cluster ions in well-defined quantum states.}, year = {2020}, type= {Article}, }
- Cate S. Anstöter, Golda Mensa-Bonsu, Pamir Nag, Miloš Ranković, Ragesh Kumar T. P., Anton N. Boichenko, Anastasia V. Bochenkova, Juraj Fedor, Jan R. R. Verlet, “Mode-Specific Vibrational Autodetachment Following Excitation of Electronic Resonances by Electrons and Photons” Physical Review Letters, vol. 124, 203401 (2020).[Bibtex]
@article{ author = {Cate S. Anstöter, Golda Mensa-Bonsu, Pamir Nag, Miloš Ranković, Ragesh Kumar T. P., Anton N. Boichenko, Anastasia V. Bochenkova, Juraj Fedor, Jan R. R. Verlet}, title = {Mode-Specific Vibrational Autodetachment Following Excitation of Electronic Resonances by Electrons and Photons}, journal = {Physical Review Letters}, volume = {124}, number = {203401}, abstract = {Electronic resonances commonly decay via internal conversion to vibrationally hot anions and subsequent statistical electron emission. We observed vibrational structure in such an emission from the nitrobenzene anion, in both the 2D electron energy loss and 2D photoelectron spectroscopy of the neutral and anion, respectively. The emission peaks could be correlated with calculated nonadiabatic coupling elements for vibrational modes to the electronic continuum from a nonvalence dipole-bound state. This autodetachment mechanism via a dipole-bound state is likely to be a common feature in both electron and photoelectron spectroscopies.}, year = {2020}, type= {Article}, }
- Xiang Huang, Juan-Pablo Aranguren, Johannes Ehrmaier, Jennifer A. Noble, Weiwei Xie, Andrzej L. Sobolewski, Claude Dedonder-Lardeux, Christophe Jouvet and Wolfgang Domcke, “Photoinduced water oxidation in pyrimidine–water clusters: a combined experimental and theoretical study” Physical Chemistry Chemical Physics, vol. 22, (2020).[Bibtex]
@article{ author = {Xiang Huang, Juan-Pablo Aranguren, Johannes Ehrmaier, Jennifer A. Noble, Weiwei Xie, Andrzej L. Sobolewski, Claude Dedonder-Lardeux, Christophe Jouvet and Wolfgang Domcke}, title = {Photoinduced water oxidation in pyrimidine–water clusters: a combined experimental and theoretical study}, journal = {Physical Chemistry Chemical Physics}, volume = {22}, number = {}, abstract = {The photocatalytic oxidation of water with molecular or polymeric N-heterocyclic chromophores is a topic of high current interest in the context of artificial photosynthesis, that is, the conversion of solar energy to clean fuels. Hydrogen-bonded clusters of N-heterocycles with water molecules in a molecular beam are simple model systems for which the basic mechanisms of photochemical water oxidation can be studied under well-defined conditions. In this work, we explored the photoinduced H-atom transfer reaction in pyrimidine–water clusters yielding pyrimidinyl and hydroxyl radicals with laser spectroscopy, mass spectrometry and trajectory-based ab initio molecular dynamics simulations. The oxidation of water by photoexcited pyrimidine is unequivocally confirmed by the detection of the pyrimidinyl radical. The dynamics simulations provide information on the time scales and branching ratios of the reaction. While relaxation to local minima of the S1 potential-energy surface is the dominant reaction channel, the H-atom transfer reaction occurs on ultrafast time scales (faster than about 100 fs) with a branching ratio of a few percent.}, year = {2020}, type= {Article}, }
- Haiwang Yong, Nikola Zotev, Jennifer M. Ruddock, Brian Stankus, Mats Simmermacher, Andrés Moreno Carrascosa, Wenpeng Du, et al., “Observation of the Molecular Response to Light upon Photoexcitation” Nature Communications, vol. 11, 1 (2020).[Bibtex]
@article{ author = {Haiwang Yong, Nikola Zotev, Jennifer M. Ruddock, Brian Stankus, Mats Simmermacher, Andrés Moreno Carrascosa, Wenpeng Du, et al.}, title = {Observation of the Molecular Response to Light upon Photoexcitation}, journal = {Nature Communications}, volume = {11}, number = {1}, abstract = {When a molecule interacts with light, its electrons can absorb energy from the electromagnetic field by rapidly rearranging their positions. This constitutes the first step of photochemical and photophysical processes that include primary events in human vision and photosynthesis. Here, we report the direct measurement of the initial redistribution of electron density when the molecule 1,3-cyclohexadiene (CHD) is optically excited. Our experiments exploit the intense, ultrashort hard x-ray pulses of the Linac Coherent Light Source (LCLS) to map the change in electron density using ultrafast x-ray scattering. The nature of the excited electronic state is identified with excellent spatial resolution and in good agreement with theoretical predictions. The excited state electron density distributions are thus amenable to direct experimental observation.}, year = {2020}, type= {Article}, }
- Sylvain Maclot, Jan Lahl, Jasper Peschel, Hampus Wikmark, Piotr Rudawski, Fabian Brunner, Hélène Coudert-Alteirac, Suvasthika Indrajith, Bernd A. Huber, Sergio Díaz-Tendero, Néstor F. Aguirre, Patrick Rousseau and Per Johnsson, “Dissociation dynamics of the diamondoid adamantane upon photoionization by XUV femtosecond pulses” Scientific Reports, vol. 10, 2884 (2020).[Bibtex]
@article{ author = {Sylvain Maclot, Jan Lahl, Jasper Peschel, Hampus Wikmark, Piotr Rudawski, Fabian Brunner, Hélène Coudert-Alteirac, Suvasthika Indrajith, Bernd A. Huber, Sergio Díaz-Tendero, Néstor F. Aguirre, Patrick Rousseau and Per Johnsson}, title = {Dissociation dynamics of the diamondoid adamantane upon photoionization by XUV femtosecond pulses}, journal = {Scientific Reports}, volume = {10}, number = {2884}, abstract = {This work presents a photodissociation study of the diamondoid adamantane using extreme ultraviolet femtosecond pulses. The fragmentation dynamics of the dication is unraveled by the use of advanced ion and electron spectroscopy giving access to the dissociation channels as well as their energetics. To get insight into the fragmentation dynamics, we use a theoretical approach combining potential energy surface determination, statistical fragmentation methods and molecular dynamics simulations. We demonstrate that the dissociation dynamics of adamantane dications takes place in a two-step process: barrierless cage opening followed by Coulomb repulsion-driven fragmentation.}, year = {2020}, type= {Article}, }