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1. Study of the Reactivity of CH3COOH+• and COOH+ Ions with CH3NH2: Evidence of the Formation of New Peptide-like C(O)−N Bonds

Author

Christian Alcaraz, Imene Derbali, R. Thissen, Emilie-Laure Zins, Claire Romanzin, Institut de Chimie Physique (ICP), and Institut de Chimie du CNRS (INC)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)

Subjects
010304 chemical physics, Formic acid, Methylamine, [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], 010402 general chemistry, Photochemistry, 01 natural sciences, Dissociation (chemistry), 0104 chemical sciences, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, chemistry.chemical_compound, Acetic acid, chemistry, 0103 physical sciences, Molecule, Peptide bond, Reactivity (chemistry), [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph], Physical and Theoretical Chemistry, Acetamide, ComputingMilieux_MISCELLANEOUS
Abstract

Acetamide, a small organic compound containing a peptide bond, was observed in the interstellar medium, but reaction pathways leading to the formation of this prebiotic molecule remain uncertain. We investigated the possible formation of a peptide-like bond from the reaction between acetic acid (CH3-COOH) and methylamine (CH3-NH2) that were identified in the interstellar medium. From an experimental point of view, a quadrupole/octopole/quadrupole mass spectrometer was used in combination with synchrotron radiation as a tunable source of VUV photons for monitoring the reactivity of selected ions. Acetic acid was photoionized, and the reactivity of CH3COOH+• as well as COOH+ (produced from either acetic acid or formic acid) ions with neutral CH3NH2 was further studied. With no surprise, charge transfer, proton transfer, and concomitant dissociation processes were found to largely dominate the reactivity. However, a C(O)-N bond formation process between the two reactants was also evidenced, with a weak cross section reaction. From a theoretical point of view, results concerning reactivity and barrier heights were obtained using density functional theory, with the LC-ωPBE range-separated functional in combination with the 6-311++G(d,p) Pople basis set and are in perfect agreement with the experimental data.

Published
2021
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2. Ultraviolet-photon fingerprints on chondritic large organic molecules

Author

Laurette Piani, Shogo Tachibana, Hiroshi Naraoka, Olivier Poch, Cédric Wolters, Iyo Sugawara, Véronique Vuitton, Frédéric Moynier, Laurène Flandinet, R. Thissen, François-Régis Orthous-Daunay, Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), 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 Grenoble Alpes [2016-2019] (UGA [2016-2019])-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 Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Centre de Recherches Pétrographiques et Géochimiques (CRPG), Institut national des sciences de l'Univers (INSU - CNRS)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), Institut de Physique du Globe de Paris (IPGP), Institut national des sciences de l'Univers (INSU - CNRS)-IPG PARIS-Université Paris Diderot - Paris 7 (UPD7)-Université de La Réunion (UR)-Centre National de la Recherche Scientifique (CNRS), Hokkaido University [Sapporo, Japan], Kyushu University [Fukuoka], The University of Tokyo (UTokyo), 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), and Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS)

Subjects
chemistry.chemical_classification, Photon, [SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], 010502 geochemistry & geophysics, medicine.disease_cause, 01 natural sciences, Astrobiology, Organic molecules, Cosmochemistry, Interstellar medium, Geophysics, Meteorite, chemistry, Geochemistry and Petrology, 0103 physical sciences, medicine, Organic matter, 010303 astronomy & astrophysics, ComputingMilieux_MISCELLANEOUS, Ultraviolet, 0105 earth and related environmental sciences
Abstract

International audience

Published
2019
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3. State-selected ion-molecule reactions with VUV synchrotron radiation : the O$_2^+$ $+$ C$_3$H$_6$ case

Author

J Lemaire, S Thomas, C Romanzin, R. Thissen, C Alcaraz, 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), Synchrotron SOLEIL (SSOLEIL), Centre National de la Recherche Scientifique (CNRS), Centre de Sciences Nucléaires et de Sciences de la Matière (CSNSM), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), and Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[PHYS]Physics [physics], History, Materials science, 010304 chemical physics, Synchrotron radiation, State (functional analysis), 010402 general chemistry, 7. Clean energy, 01 natural sciences, 0104 chemical sciences, Computer Science Applications, Education, Ion, 0103 physical sciences, Molecule, Atomic physics, Physics::Chemical Physics
Abstract

Synopsis O2 + molecular ion is produced by photoionization close to threshold at SOLEIL, DESIRS beam line. By means of coincidence methods, ions are prepared in selected vibrational and electronic states (X, v=0,3,15 and a, v=3). Their reactivity with the propene in single collision regime is studied in the guided ion beam in-strument CERISES, adding ability to vary the collision energy. Absolute reaction cross section and branching ratio are recorded for the 5 most intense reactive channels, described as dissociative charge transfer. Contrasted effects of internal and collision energy are observed.

Published
2019
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4. Identification of organic molecules with a laboratory prototype based on the Laser Ablation-CosmOrbitrap

Author

P. Zapf, Gilles Chalumeau, Motoo Ito, Alexander Makarov, F. Colin, Laura Selliez, Nicolas Fray, S. Ruocco, B. Gaubicher, R. Thissen, François-Régis Orthous-Daunay, Laurent Thirkell, Noël Grand, Hervé Cottin, Cécile Engrand, Laurène Flandinet, Jean-Pierre Lebreton, Cyril Szopa, Véronique Vuitton, Nathalie Carrasco, C. Briois, Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Centre National d’Études Spatiales [Paris] (CNES), IMPEC - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Institut Universitaire de France (IUF), Ministère de l'Education nationale, de l’Enseignement supérieur et de la Recherche (M.E.N.E.S.R.), Laboratoire de Chimie Physique D'Orsay (LCPO), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), Kochi Institute for Core Sample Research, Japan Agency for Marine-Earth Science and Technology (JAMSTEC), 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), Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA (UMR_7583)), Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Centre de Sciences Nucléaires et de Sciences de la Matière (CSNSM), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Thermo Fisher Scientific (Bremen) GmbH, Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), CNES (Centre National d’Etudes Spatiales) and the Région Centre-Val de Loire for the funding of her PhD., European Project: 636829,H2020,ERC-2014-STG,PRIMCHEM(2015), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), PLANETO - LATMOS, Sorbonne Université (SU)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Université Paris-Sud - Paris 11 (UP11)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), 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 Grenoble Alpes [2016-2019] (UGA [2016-2019])-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 Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS), Sorbonne Université (SU)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Centre National de la Recherche Scientifique (CNRS), and Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Institut national des sciences de l'Univers (INSU - CNRS)

Subjects
Materials science, 010504 meteorology & atmospheric sciences, Analyser, FOS: Physical sciences, High mass resolution, Mass spectrometry, Orbitrap, 01 natural sciences, 7. Clean energy, Space mass spectrometry, Space exploration, law.invention, law, 0103 physical sciences, Aerospace engineering, Aerospace, Enceladus, 010303 astronomy & astrophysics, Instrumentation and Methods for Astrophysics (astro-ph.IM), 0105 earth and related environmental sciences, Earth and Planetary Astrophysics (astro-ph.EP), Chemical identification, Laser ablation, business.industry, Astronomy and Astrophysics, Mars Exploration Program, Astrobiology, [SDU.ASTR.IM]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Instrumentation and Methods for Astrophysic [astro-ph.IM], CosmOrbitrap, 13. Climate action, Space and Planetary Science, business, Astrophysics - Instrumentation and Methods for Astrophysics, [CHIM.OTHE]Chemical Sciences/Other, Astrophysics - Earth and Planetary Astrophysics
Abstract

International audience; In the Solar System, extra-terrestrial organic molecules have been found on cometary primitive objects, on Titan and Enceladus icy moons and on Mars. Identification could be achieved for simple organic species by remote sensing based on spectroscopic methods. However in situ mass spectrometry is a key technology to determine the nature of more complex organic matter. A large panel of mass spectrometers has already been developed for space exploration combining different types of analysers and ion sources. Up to now the highest mass resolution reached with a space instrument is 9,000 at m/z 28 and corresponds to the DFMS-ROSINA instrument (Balsiger et al., 2007) dedicated to the study of the comet 67P/Churyumov-Gerasimenko's atmosphere and ionosphere, in a low pressure environment. A new concept of mass analyser offering ultra-high mass resolving power of more than 50,000 at m/z 56 (under high vacuum condition about 10−9 mbar) is currently being developed for space applications: the CosmOrbitrap (Briois et al., 2016), based on the Orbitrap™ technology.This work challenges the use of LAb-CosmOrbitrap, a space instrument prototype combining Laser Ablation ionisation and the CosmOrbitrap mass analyser, to identify solid organic molecules of relevance to the future space exploration. For this purpose a blind test was jointly organised by the JAXA-HRMS team (Japan Aerospace Exploration Agency-High Resolution Mass Spectrometry) and the CosmOrbitrap consortium. The JAXA team provided two organic samples, whereas the CosmOrbitrap consortium analysed them without prior information. Thanks to the high analytical performances of the prototype and our HRMS data post-processing, we successfully identified the two molecules as HOBt, hydroxybenzotriazole (C6H5N3O) and BBOT, 2,5-Bis(5-tert-butyl-benzoxazol-2-yl)thiophene (C26H26N2O2S), with a mass resolving power of, respectively, 123 540 and 69 219. The success of this blind test on complex organic molecules shows the strong potential of LAb-CosmOrbitrap for future space applications.

Published
2019
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5. Physical and chemical properties of dust produced in a N2-CH4 RF plasma discharge

Author

F. Ouni, G. Adande, R. Thissen, G. Alcouffe, C. Szopa, I. Schmitz-Afonso, O. Laprévote, E. Quirico, O. Brissaud, N. Carrasco, G. Cernogora, José Tito Mendonça, David P. Resendes, Padma K. Shukla, Service d'aéronomie (SA), 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 Planétologie de Grenoble (LPG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut de Chimie des Substances Naturelles (ICSN), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), J.T. Mendonça, D.P. Resendes and P.K. Shukla, Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), and Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)

Subjects
010504 meteorology & atmospheric sciences, Analytical chemistry, Infrared spectroscopy, plasma radiofrequency heating, Mass spectrometry, 01 natural sciences, 7. Clean energy, Fourier transform spectroscopy, symbols.namesake, plasma chemistry, [PHYS.PHYS.PHYS-PLASM-PH]Physics [physics]/Physics [physics]/Plasma Physics [physics.plasm-ph], 0103 physical sciences, Capacitively coupled plasma, Fourier transform infrared spectroscopy, 010303 astronomy & astrophysics, dusty plasmas, 0105 earth and related environmental sciences, Chemistry, Plasma, 13. Climate action, Atmospheric chemistry, symbols, Titan (rocket family), aerosols, polymerisation
Abstract

Titan’s atmospheric chemistry is simulated using a Capacitively Coupled Plasma discharge produced in a N2‐CH4 mixture. The produced solid particles are analysed ex‐situ. Chemical properties are deduced from: elemental composition, FTIR and LTQ‐Orbitrap mass spectrometer. Optical properties are deduced from reflectivity in visible and IR range.

Published
2008
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6. An experimental study of the reactivity of CN- and C3N- anions with cyanoacetylene (HC3N)

Author

Joël Lemaire, Claire Romanzin, Essyllt Louarn, Jean-Claude Guillemin, Christian Alcaraz, Ján Žabka, Miroslav Polášek, 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), J. Heyrovský Institute of Physical Chemistry, Prague, Institut des Sciences Chimiques de Rennes (ISCR), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), This work has been supported by the French National Program of Planetology, the 'Triangle de la Physique' – FCS Campus Paris Saclay under the contract n° 2012-027T-GIN, the COST program Action CM0805 'The Chemical Cosmos: Understanding Chemistry in Astronomical Environments', the COST program Action TD1308 'Origins and Evolution of Life on Earth and in the Universe', the Czech Science Foundation (Grant No. 14-19693S) and the Ministry of Youth and Sports of Czech Republic (Grant No. LD14024).The authors acknowledge their collaborators V. Vuitton, R. Thissen, S. Le Picard, L. Biennier and S. Carles for valuable discussions. C.A. and C.R. thank J.-C. Loison for his help with the calculations. J.-C. G. thanks the Centre National d’Etudes Spatiales (CNES) for financial support., Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), and Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)

Subjects
Anions, Proton, FTICR-MS, Cyanide, Kinetics, Analytical chemistry, Ionic bonding, 010402 general chemistry, 01 natural sciences, Ion, chemistry.chemical_compound, Reaction rate constant, 0103 physical sciences, Cyanoacetylene, [CHIM]Chemical Sciences, Reactivity (chemistry), Ionosphere, 010303 astronomy & astrophysics, Cyanoacetylide, Reactivity, Astronomy and Astrophysics, 0104 chemical sciences, Chemistry, chemistry, 13. Climate action, Space and Planetary Science, Atomic physics, Experiments, Titan
Abstract

The reactions of the CN − and C 3 N − anions with cyanoacetylene HC 3 N, of special interest for the chemistry of Titan’s upper atmosphere, have been investigated by means of FTICR mass-spectrometry. Primary ions, CN − and C 3 N − , have been produced by dissociative electron attachment (DEA) from BrCN and BrC 3 N, and prepared in a clean way before reaction. Total rate constants have been measured for both reactions at 300 K and are found to be as follows: (3.9 ± 0.5) × 10 −9 and (1.0 ± 0.2) × 10 −10 cm 3 s −1 for the reaction of HC 3 N with CN − and C 3 N − , respectively. For the CN − + HC 3 N reaction, proton transfer is found to be the only reactive channel within our detection limits. Proton transfer is also dominant for the C 3 N − + HC 3 N reaction but the resulting ionic product being identical to the primary ion C 3 N − , this process is transparent for the kinetics of the C 3 N − + HC 3 N reaction and the kinetic rate retrieved corresponds to a slow and competitive detachment pathway. Yet the nature and energetics of the neutral product(s) formed through this process remain unknown. Additional experiments using isotopic products have allowed to retrieve specific rate constants associated with the proton transfer channel in the C 3 15 N − + HC 3 N and C 3 N − + HC 3 15 N reactions and the measured rates are found to be significantly lower than for the CN − + HC 3 N system. This decrease and the evolution of reactivity when going from CN − to C 3 N − and the opening of a new detachment pathway are finally discussed.

Published
2016
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