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1. Experimental and computational studies on the reactivity of methanimine radical cation (H$_2$CNH$^{+\cdot}$) and its isomer aminomethylene (HCNH$_2^{+\cdot}$) with C$_2$H$_2$

Author

Richardson, Vincent, Ascenzi, Daniela, Sundelin, David, Alcaraz, Christian, Romanzin, Claire, Thissen, Roland, Guillemin, Jean-Claude, Polášek, Miroslav, Tosi, Paolo, Žabka, Jan, and Geppert, Wolf D.

Subjects
Physics - Chemical Physics, Astrophysics - Earth and Planetary Astrophysics, Astrophysics - Astrophysics of Galaxies, Astrophysics - Solar and Stellar Astrophysics
Abstract

Experimental and theoretical studies are presented on the reactivity of the radical cation isomers methanimine and aminomethylene with ethyne. Selective isomer generation is performed via dissociative photoionization of suitable neutral precursors and via direct photoionization of methanimine. Reactive cross sections and product branching ratios are measured as a function of photon and collision energies. Results are discussed in light of ab initio calculations of reaction mechanisms. The major channels, for both isomers, are due to H atom elimination from covalently bound adducts to give [C3NH4]+. Theoretical calculations show that while for the reaction of aminomethylene with acetylene any of the three lowest energy [C3NH4]+ isomers can form via barrierless and exothermic pathways, for the methanimine reagent the only barrierless pathway is the one leading to the production of protonated vinyl cyanide (CH2CHCNH+), a prototypical branched nitrile species that has been proposed as a likely intermediate in star forming regions and in the atmosphere of Titan. The astrochemical implications of the results are briefly addressed., Comment: 16 pages, 8 figures, 2 Tables. Supplementary material available at Publisher's site

Published
2021
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2. The reactivity of methanimine radical cation (H$_2$CNH$^{+\cdot}$) and its isomer aminomethylene (HCNH$_2^{+\cdot}$) with C$_2$H$_4$

Author

Sundelin, David, Ascenzi, Daniela, Richardson, Vincent, Alcaraz, Christian, Polášek, Miroslav, Romanzin, Claire, Thissen, Roland, Tosi, Paolo, Žabka, Jan, and Geppert, Wolf D.

Subjects
Physics - Chemical Physics, Astrophysics - Astrophysics of Galaxies, Astrophysics - Solar and Stellar Astrophysics
Abstract

Experimental and theoretical studies are presented on the reactivity of methanimine and aminomethylene cations with ethene. Selective isomer generation is performed via dissociative photoionization of suitable neutral precursors and reactive cross sections and branching ratios are measured as a function of photon and collision energies., Comment: 15 pages, 6 figures, 2 Tables

Published
2021
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7. OLYMPIA-LILBID: High Resolution Mass Spectrometry for the Calibration of Spaceborne Hypervelocity Ice Grain Detector

Author

Sanderink, Arnaud, primary, Klenner, Fabian, additional, Zabka, Jan, additional, Postberg, Frank, additional, Lebreton, Jean-Pierre, additional, Zymak, Illia, additional, Bertrand, Gaubicher, additional, Abel, Bernd, additional, Charvat, Ales, additional, Cherville, Barnabé, additional, Thirkell, Laurent, additional, and Briois, Christelle, additional

Published
2022
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8. HANKA - cubesat space high resolution mass analyser

Author

Zabka, Jan, primary, Polášek, Miroslav, additional, Zymak, Ylja, additional, Lacko, Michal, additional, Sixtová, Nikola, additional, Lebreton, Jean-Pierre, additional, Sanderink, Arnaud, additional, and Kashkoul, Marwa, additional

Published
2022
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19. Krakow Can Breathe Again.

Author

Zabka, Jan

Subjects
*CITY dwellers, *AIR pollutants, *GLOBAL warming, *ENVIRONMENTAL organizations, *YOUNG adults, *PETITIONS
Abstract

Krakow, Poland has made significant progress in improving its air quality, thanks in part to the efforts of the environmental organization Krakow Smog Alarm. Through public campaigns and pressure on politicians, the organization successfully convinced the local government to implement a ban on solid fuels, leading to a reduction in smog days and improved air quality. However, the ban has not been implemented throughout the entire region and remains controversial in some areas. In contrast, the Czech city of Ostrava still struggles with air pollution, primarily due to solid-fuel heating, and does not currently have plans for a complete ban. [Extracted from the article]

Published
2024

20. Reactivity of the CHBr(super 2+) dication toward molecular hydrogen

Author

Roithova, Jana, Zabka, Jan, Herman, Zdenek, Thissen, Roland, Schribder, Detlef, and Schwarz, Helmut

Subjects
Methyl groups -- Atomic properties, Methyl groups -- Chemical properties, Bromine -- Atomic properties, Bromine -- Chemical properties, Chemicals, plastics and rubber industries
Abstract

Structural aspects as well as the stability and reactivity of the CHB(r.sup.2+) dication are studied experimentally and theoretically. Translational energy distributions of the CHB(r.sup.+) products from charge transfer between CHB(r.sup.2+) and Kr indicate that the dication exists in two isomeric forms, H-C-B(r.sup.2+) and C-Br-(H.sup.2+).

Published
2006

21. Collisions of slow polyatomic ions with surfaces: Dissociation and chemical reactions of C(sub 2)H(sub 2)(super +.), C(sub 2)H(sub 4)(super +), C(sub 2)H(sub 4)(super +.), C(sub 2)H(sub 5)(super +), and their deuterated variants C(sub 2)D(sub 2)(super +.) and C(sub 2)D(sub 4)(super +.) on room-temperature and heated carbon surfaces

Author

Jasik, Juraj, Zabka, Jan, Feketeova, Linda, Ipolyi, Imre, Mark, Tilmann D., and Herman, Zdenek

Subjects
Acetylene -- Chemical properties, Olefins -- Chemical properties, Ethylene -- Chemical properties, Chemicals, plastics and rubber industries
Abstract

Study is carried out to investigate the interaction of C(sub 2)H(sub n)(super +) (n = 2-5) hydrocarbon ions and some of their isotopic variants with room-temperature and heated highly oriented pyrolytic graphite (HOPG) surfaces. Results of scattering experiments on collisions of C(sub 2)H((super +.) (C(sub 2)D(sub 2)(super +.)), C(sub 2)H(sub 3)(super +), C(sub 2)H(sub 4)(super +.), and C(sub 2)H(sub 5)(super +) with room-temperature and heated surfaces of highly oriented pyrolytic graphite in the collision energy range 10-45 eV are reported.

Published
2005

22. (super 15)N(super +) + CD4 and O(super +) + (super 13)CO2 state-selected ion-molecule reactions relevant to the chemistry of planetary ionospheres

Author

Alcaraz, Christian, Nicolas, Christophe, Thissen, Roland, Zabka, Jan, and Dutuit, Odile

Subjects
Oxygen -- Atomic properties, Dissociation -- Analysis, Nitrogen compounds -- Atomic properties, Chemicals, plastics and rubber industries
Abstract

The dissociation photoionization of N2 and O2 by synchrotron radiation in coincidence with threshold photoelectrons was used to produce state-selected N(super +) and O(super +) ions to study their reactivity. The method can produce pure reactant ions without broadening their translational energy, which is important for the study of reaction dynamics.

Published
2004

29. Crossed-beam scattering studies of electron-transfer processes between the dication C[[O.sub.2].sup.2+] and neutral C[O.sub.2]: electronic states of reactants and products ijnvolved

Author

Zabka, Jan, Ricketts, Claire L., Schroder, Detlef, Roithova, Jana, Schwarz, Helmut, Thissen, Roland, Dutuit, Odile, Price, Stephen D., and Herman, Zdenek

Subjects
Collisions (Nuclear physics) -- Analysis, Carbon dioxide -- Structure, Carbon dioxide -- Chemical properties, Carbon dioxide -- Electric properties, Dissociation -- Analysis, Electrons -- Scattering, Electrons -- Analysis, Chemicals, plastics and rubber industries
Published
2010

30. Threshold photoelectron spectroscopy of the methyl radical isotopomers, C[H.sub.3], C[H.sub.2]D, CH[D.sub.2] and C[D.sub.3]: synergy between VUV synchrotron radiation experiments and explicitly correlated coupled cluster calculations

Author

Cunha de Miranda, Barbara K., Alcaraz, Christian, Elhanine, Mohamed, Noller, Bastian, Hemberger, Patrick, Fischer, Ingo, Garcia, Gustavo A., Soldi-Lose, Heloise, Gans, Berenger, Vieira Mendess., Luiz A., Boye-Peronne, Sverine, Douin, Stephane, Zabka, Jan, and Botschwina, Peter

Subjects
Ionization -- Analysis, Methyl groups -- Chemical properties, Methyl groups -- Optical properties, Photoelectron spectroscopy -- Usage, Pyrolysis -- Analysis, Synchrotron radiation -- Usage, Chemicals, plastics and rubber industries
Published
2010

31. Dynamics of formation of products [D.sub.2]C[N.sup.+], DC[N.sup.+], and C[[D.sub.3].sup.+] in the reaction of [N.sup.+] with C[D.sub.4]: a crossed-beam and theoretical study

Author

Zabka, Jan, Roithova, Jana, Spanel, Patrik, and Herman, Zdenek

Subjects
Nitrogen -- Chemical properties, Nitrogen -- Electric properties, Scattering (Physics) -- Analysis, Cyanides -- Chemical properties, Deuterium -- Chemical properties, Deuterium -- Electric properties, Chemicals, plastics and rubber industries
Published
2010

32. Correlations between survival probabilities and ionization energies of slow ions colliding with room-temperature and heated surfaces of carbon, tungsten, and beryllium

Author

Herman, Zdenek, Zabka, Jan, and Pysanenko, Andriy

Subjects
Beryllium -- Chemical properties, Beryllium -- Thermal properties, Carbon -- Chemical properties, Carbon -- Thermal properties, Hydrocarbons -- Chemical properties, Hydrocarbons -- Thermal properties, Ionization energy -- Analysis, Tungsten -- Chemical properties, Tungsten -- Thermal properties, Chemicals, plastics and rubber industries
Published
2009

33. Bond-forming reactions of dications with molecules: A computational and experimental study of the mechanisms for the formation of HC[F.sub.2.sup.+] from C[F.sub.3.sup.2+] and [H.sub.2]

Author

Lambert, Natalie, Kaltsoyannis, Nikolas, Price, Stephen D., Zabka, Jan, and Herman, Zdenek

Subjects
Cations -- Chemical properties, Cations -- Atomic properties, Computational chemistry -- Research, Chemicals, plastics and rubber industries
Abstract

The QCISD and QCISD(T) quantum chemical methods are used to characterize the energetics of various mechanisms for the formation of HC[F.sub.2.sup.+] from the bond-forming reaction of C[F.sub.3.sup.2+] with [H.sub.2]. The experimentally determined kinetic energy releases for both the channels are in good agreement with the calculated mechanisms leading to the product asymptotes.

Published
2006

34. Dynamics of chemical and charge-transfer reactions of molecular dications. IV. Proton transfer and reactions of dication isomers in the CHCl(super 2+) + D2 system

Author

Roithova, Jana, Zabka, Jan, Hrusak, JAn, Thissen, Roland, and Herman, Zdenek

Subjects
Chemistry, Physical and theoretical -- Research, Charge transfer -- Research, Chemical reactions -- Research, Chemicals, plastics and rubber industries
Abstract

Chemical reactions and charge-transfer processes in the CHCl(super 2+) +D2 systems are investigated in crossed-beam scattering experiments. Theoretical calculations of the energetics of the species involved complements the experimental data and the calculations of stationary points on the dication potential energy surfaces support the experimental data.

Published
2003

35. Energy partitioning in collisions of slow polyatomic ions with surfaces: ethanol molecular ions on surfaces covered by self-assembled monolayers (CF-SAM, CH-SAM, COOH-SAM)

Author

Zabka, Jan, Dolejsek, Zdenek, and Herman, Zdenek

Subjects
Energy transfer -- Analysis, Carbon -- Chemical properties, Hydrocarbons -- Chemical properties, Alcohol -- Chemical properties, Alcohol, Denatured -- Chemical properties, Chemicals, plastics and rubber industries
Abstract

Energy transfer in ion-surface interactions between ethanol molecular ion and self-assembled monolayers formed by perfluoro-hydrocarbon (CF-SAM), hydrocarbon (CH-SAM), and hydrocarbon with terminal -COOH group C11 or C12 chains were investigated over the incident energy rate of 11-32 eV for several incident angles.

Published
2002

36. Collisions of slow polyatomic ions with surfaces: dissociation and chemical reactions of CD5(super +), CD4(super +), CD3(super +), and their isotopic variants on room-temperature and heated carbon surfaces

Author

Roithova, Jana, Zabka, Jan, Dolejsek, Zdenek, and Herman, Zdenek

Subjects
Chemical reactions -- Research, Chemistry, Physical and theoretical -- Research, Collisions (Physics) -- Research, Chemicals, plastics and rubber industries
Abstract

A study was conducted to investigate the interaction of small hydrocarbon ions, CD3(super +), CD4(super +), CD5(super +), and their isotopic variants CH(sub n)(super +) and (super 13)CH(sub n)(super +) (n = 3,4,5), with room temperature and heated carbon surfaces, over the collision energy range 16-52 eV. The result shows the ion survival probability to about 10% for CD5(super +) and about 30-60 times smaller (0.2-0.4%) for CD3(super +) and CD4(super +).

Published
2002

37. Is the Reaction of C3N- with C2H2 a Possible Process for Chain Elongation in Titan's Ionosphere?

Author

Lindén, Fredrik, Alcaraz, Christian, Ascenzi, Daniela, Guillemin, Jean-Claude, Koch, Leopold, Lopes, Allan, Polášek, Miroslav, Romanzin, Claire, Zabka, Jan, Zymak, Illia, Geppert, Wolf D., Lindén, Fredrik, Alcaraz, Christian, Ascenzi, Daniela, Guillemin, Jean-Claude, Koch, Leopold, Lopes, Allan, Polášek, Miroslav, Romanzin, Claire, Zabka, Jan, Zymak, Illia, and Geppert, Wolf D.

Abstract

The reaction of C3N- with acetylene was studied using three different experimental setups, a triple quadrupole mass spectrometer (Trento), a tandem quadrupole mass spectrometer (Prague), and the CERISES guided ion beam apparatus at Orsay. The process is of astrophysical interest because it can function as a chain elongation mechanism to produce larger anions that have been detected in Titan's ionosphere by the Cassini Plasma Spectrometer. Three major products of primary processes, C2H-, CN-, and C5N-, have been identified, whereby the production of the cyanide anion is probably partly due to collisional induced dissociation. The formations of all these products show considerable reaction thresholds and also display comparatively small cross sections. Also, no strong signals of anionic products for collision energies lower than 1 eV have been observed. Ab initio calculations have been performed to identify possible pathways leading to the observed products of the title reaction and to elucidate the thermodynamics of these processes. Although the productions of CN- and C5N- are exoergic, all reaction pathways have considerable barriers. Overall, the results of these computations are in agreement with the observed reaction thresholds. Due to the existence of considerable reaction enenrgy barriers and the small observed cross sections, the title reaction is not very likely to play major role in the buildup of large anions in cold environments like the interstellar medium or planetary and satellite ionospheres.

Published
2016
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38. Dynamics of chemical and charge-transfer reactions of molecular dications: III. Beam scattering and total cross section data for processes in the system CO2(super 2+) +D2

Author

Mrazek, Libor, Zabka, Jan, Dolejsek, Zdenek, Hrusak, Jan, and Herman, Zdenek

Subjects
Carbon compounds -- Chemical properties, Carbon compounds -- Electric properties, Charge transfer -- Research, Chemical reactions -- Research, Chemistry, Physical and theoretical -- Research, Chemicals, plastics and rubber industries
Abstract

Chemical reactions and charge-transfer processes in the system CO2(super 2+) + D2 is investigated in crossed-beam scattering experiments. The chemical product CO2D(super +) is formed in a nondissociative chemical reaction leading to CO2D(super +) + D(super +) through two channels that released different amounts of translational energy through decomposition of intermediates.

Published
2000

39. Critical Review of N, N+, N+ 2, N++, and N++ 2 Main Production Processes and Reactions of Relevance to Titan's Atmosphere

Author

Dutuit, Odile, Carrasco, Nathalie, Thissen, Roland, Vuitton, Véronique, Alcaraz, Christian, Pernot, Pascal, Balucani, Nadia, Casavecchia, Piergiorgio, Canosa, André, Le Picard, Sébastien D., Loison, Jean-Christophe, Herman, Zdenek, Zabka, Jan, Ascenzi, Daniela, Tosi, Paolo, Franceschi, Pietro, Price, Stephen D., Lavvas, Panayotis, Institut de Planétologie et d'Astrophysique de Grenoble (IPAG ), Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Space Research Institute of Austrian Academy of Sciences (IWF), Austrian Academy of Sciences (OeAW), PLANETO - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Chimie Physique D'Orsay (LCPO), Université Paris-Sud - Paris 11 (UP11)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Dipartimento di Chimica [Perugia], Università degli Studi di Perugia (UNIPG), Institut de Physique de Rennes (IPR), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences Moléculaires (ISM), Centre National de la Recherche Scientifique (CNRS)-École Nationale Supérieure de Chimie et de Physique de Bordeaux (ENSCPB)-Université Sciences et Technologies - Bordeaux 1-Université Montesquieu - Bordeaux 4-Institut de Chimie du CNRS (INC), J. Heyrovský Institute of Physical Chemistry of the ASCR, Czech Academy of Sciences [Prague] (CAS), Dipartimento di Fisica [Povo], Università degli Studi di Trento (UNITN), IASMA Research and Innovation Centre, Istituto Agrario di San Michele All'Adige, Department of Chemistry [UCL, London], University College of London [London] (UCL), Groupe de spectrométrie moléculaire et atmosphérique (GSMA), Université de Reims Champagne-Ardenne (URCA)-Centre National de la Recherche Scientifique (CNRS), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), IMPEC - LATMOS, Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), Université Montesquieu - Bordeaux 4-Université Sciences et Technologies - Bordeaux 1-École Nationale Supérieure de Chimie et de Physique de Bordeaux (ENSCPB)-Centre National de la Recherche Scientifique (CNRS), Czech Academy of Sciences [Prague] (ASCR), Università degli Studi di Perugia = University of Perugia (UNIPG), Université de Rennes (UR)-Centre National de la Recherche Scientifique (CNRS), and Université Montesquieu - Bordeaux 4-Université Sciences et Technologies - Bordeaux 1 (UB)-École Nationale Supérieure de Chimie et de Physique de Bordeaux (ENSCPB)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)

Subjects
astrochemistry, dinitrogen processes, astrochemistry, Molecular data, [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], TheoryofComputation_ANALYSISOFALGORITHMSANDPROBLEMCOMPLEXITY, [SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], Planets and satellites: atmospheres, Atomic processes, dinitrogen processes, Titan, Molecular processes, Atomic data
Abstract

International audience; This paper is a detailed critical review of the production processes and reactions of N, N+, N+ 2, N++, and N++ 2 of relevance to Titan's atmosphere. The review includes neutral, ion-molecule, and recombination reactions. The review covers all possible active nitrogen species under Titan's atmospheric conditions, specifically N2 (A3Σ+ u), N (4 S), N (2 D), N (2 P), N+ 2, N+ (3 P), N+ (1 D), N++ 2, and N++ species, and includes a critical survey of the reactions of N, N+, N+ 2, N++, and N++ 2 with N2, H2, D2, CH4, C2H2, C2H4, C2H6, C3H8 and the deuterated hydrocarbon analogs, as well as the recombination reactions of N+ 2, N+, N++ 2, and N++. Production processes, lifetimes, and quenching by collisions with N2 of all reactant species are reviewed. The N (4 S) state is reactive with radicals and its reactions with CH2, CH3, C2H3, and C2H5 are reviewed. Metastable states N2(A3Σ+u), N (2 D), and N (2 P) are either reactive or quenched by collisions with the target molecules reviewed. The reactions of N+ (1 D) have similar rate constants as N+ (3 P), but the product branching ratios differ significantly. Temperature effects and the role of the kinetic energy content of reactants are investigated. In all cases, experimental uncertainties of laboratory data are reported or estimated. Recommended values with uncertainties, or estimated values when no data are available, are given for rate constants and product branching ratios at 300 K and at the atmospheric temperature range of Titan (150-200 K for neutral reactions and 150 K for ion reactions).

Published
2013
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40. Dynamics of chemical and charge transfer reactions of molecular dications: VI: Reactions of C4H32+ with Kr, Xe, H2, N2, NO, NH3, C2H2, and CH4

Author

Jasik, Juraj, Roithová, Jana, Zabka, Jan, Thissen, Roland, Ipolyi, Imre, Herman, Zdenek, V. Čermák Laboratory, Czech Academy of Sciences [Prague] (CAS)-J. Heyrovsky Institute of Physical Chemistry, Department of Experimental Physics [UNIBA Bratislava], Faculty of Mathematics, Physics and Informatics [Bratislava] (FMPH/UNIBA), Comenius University in Bratislava-Comenius University in Bratislava, Laboratoire de Chimie Physique D'Orsay (LCPO), and Université Paris-Sud - Paris 11 (UP11)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Molecular dications, Charge transfer, Reaction dynamics, Physics::Chemical Physics, Proton transfer
Abstract

International audience; Reactions of the hydrocarbon dication C4H32+ with a series of atomic and molecular targets (Kr, Xe, N2, NO, NH3, C2H2, and CH4) were investigated in crossed-beam scattering and guided-beam (quadrupole–octopole–quadrupole, QOQ) experiments. Non-dissociative charge transfer (NDCT), leading to the product ion C4H3+, and proton transfer (PT), leading to the product ion C4H2+, were observed. In several systems, however, dissociative charge transfer (DCT) contributed significantly to the formation of the product ion C4H2+. Full scattering diagrams of the products C4H3 and C4H2+ were obtained for the reaction with acetylene. For the other systems, energy profiles of the products close to the angular maximum were obtained. The hydrocarbon products C4H2+ and C4H3+ were scattered mostly forward, suggesting an impulsive mechanism of their formation at the collision energies investigated; the only exception was proton transfer with H2, where the energy profile of C4H2+ indicated substantial backward scattering and formation of an intermediate. From relative translational energy distributions of the products, conclusions could be made about electronic states of the hydrocarbon cations formed in these reactions.

Published
2006
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41. CRITICAL REVIEW OF N, N + , N + 2 , N ++ , And N ++ 2 MAIN PRODUCTION PROCESSES AND REACTIONS OF RELEVANCE TO TITAN'S ATMOSPHERE

Author

Dutuit, Odile, primary, Carrasco, Nathalie, additional, Thissen, Roland, additional, Vuitton, Véronique, additional, Alcaraz, Christian, additional, Pernot, Pascal, additional, Balucani, Nadia, additional, Casavecchia, Piergiorgio, additional, Canosa, André, additional, Picard, Sébastien Le, additional, Loison, Jean-Christophe, additional, Herman, Zdenek, additional, Zabka, Jan, additional, Ascenzi, Daniela, additional, Tosi, Paolo, additional, Franceschi, Pietro, additional, Price, Stephen D., additional, and Lavvas, Panayotis, additional

Published
2013
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42. Prophets of Freedom and Doom - Transitions.

Author

Cherici, Sofia and Zabka, Jan

Subjects
*CONSPIRACY theories, *OPTIMISM, *QANON, *SOCIAL media, *CLIMATE change denial, *PROPHETS
Abstract

B New Age Pan-Slavism b In the Czech and Slovak Republics, conspiracy theories spread through different channels, but especially on the social network Telegram, which, in these countries, is used mainly by extremists, QAnon followers, and devotees of disinformation news streams. Here, while conspiracy influencers benefit from QAnon - as it mobilizes their fan base - QAnon benefits in terms of diffusion from its communion with the pan-Slavic ideology. AllatRa, Central Europe, conspiracy, Eastern Europe, pan-Slavism, extremism, social media, QAnon Keywords: AllatRa; Central Europe; conspiracy; Eastern Europe; extremism; pan-Slavism; QAnon; social media EN AllatRa Central Europe conspiracy Eastern Europe extremism pan-Slavism QAnon social media N.PAG N.PAG 1 03/08/23 20230306 NES 230306 I A mishmash of "positive thinking" spiced with pan-Slavism, far-out conspiracy theories, and apocalyptic visions is a growing presence on Central European social media. i Today, the web seems to have a problem with the circulation of far-right content. [Extracted from the article]

Published
2023

46. CRITICAL REVIEW OF N, N+,N2+,N++,And N2++ MAIN PRODUCTION PROCESSES AND REACTIONS OF RELEVANCE TO TITAN'S ATMOSPHERE.

Author

DUTUIT, ODILE, CARRASCO, NATHALIE, THISSEN, ROLAND, VUITTON, VÉRONIQUE, ALCARAZ, CHRISTIAN, PERNOT, PASCAL, BALUCANI, NADIA, CASAVECCHIA, PIERGIORGIO, CANOSA, ANDRÉ, LE PICARD, SÉBASTIEN, LOISON, JEAN-CHRISTOPHE, HERMAN, ZDENEK, ZABKA, JAN, ASCENZI, DANIELA, TOSI, PAOLO, FRANCESCHI, PIETRO, PRICE, STEPHEN D., and LAVVAS, PANAYOTIS

Published
2013
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49. State-specific reactions and autoionization dynamics of Ar2+ produced by synchrotron radiation

Author

Franceschi, Pietro, Thissen, Roland, Dutuit, Odile, Alcaraz, Christian, Soldi-Lose, Heloise, Bassi, Davide, Ascenzi, Daniela, Tosi, Paolo, Zabka, Jan, Herman, Zdenek, Coreno, Marcello, and de Simone, Monica

Subjects
*CHEMICAL reactions, *EXCITED state chemistry, *SYNCHROTRON radiation, *AUGER effect, *CHARGE transfer, *CATIONS
Abstract

Abstract: The long-lived excited states of doubly charged rare gases can markedly affect their reactivity. In this paper we demonstrate the presence of strong state-specific effects in the charge exchange of Ar2+ (3P, 1D and 1S) with several neutral targets (He, Ne, Kr, Xe, D2, and CH4). State sensitive measurements have been performed by producing the different Ar2+ electronic states via tunable synchrotron radiation (Elettra-Trieste, Italy and SuperACO-Orsay, France). From the product ion yield data of charge transfer, state-selected total cross-sections have been deduced. Using the state-specific reactivity of Ar2+ towards different neutral targets, it has been possible to extract the photon-energy-dependent production branching of the three doubly charged states and to investigate the autoionization dynamics of neutral or singly charged Ar in the vicinity of the double ionization threshold. [Copyright &y& Elsevier]

Published
2009
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50. Formation of organoxenon dications in the reactions of xenon with dications derived from toluene.

Author

Zins EL, Milko P, Schröder D, Aysina J, Ascenzi D, Zabka J, Alcaraz C, Price SD, and Roithová J

Abstract

The bimolecular reactivity of xenon with C(7)H(n)(2+) dications (n=6-8), generated by double ionization of toluene using both electrons and synchrotron radiation, is studied by means of a triple-quadrupole mass spectrometer. Under these experimental conditions, the formation of the organoxenon dications C(7)H(6)Xe(2+) and C(7)H(7)Xe(2+) is observed to occur by termolecular collisional stabilization. Detailed experimental and theoretical studies show that the formation of C(7)H(6)Xe(2+)+H(2) from doubly ionized toluene (C(7)H(8)(2+)) and xenon occurs as a slightly endothermic, direct substitution of dihydrogen by the rare gas with an expansion to a seven-membered ring structure as the crucial step. For the most stable isomer of C(7)H(6)Xe(2+), an adduct between the cycloheptatrienyldiene dication and xenon, the computed binding energy of 1.36 eV reaches the strength of (weak) covalent bonds. Accordingly, electrophiles derived from carbenes might be particularly promising candidates in the search for new rare-gas compounds., (Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Published
2011
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