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Ayasli A, Khan A, Michaelsen T, Gstir T, Ončák M, Wester R. Imaging Frontside and Backside Attack in Radical Ion-Molecule Reactive Scattering. J Phys Chem A 2023. [PMID: 37354118 DOI: 10.1021/acs.jpca.3c02856] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/26/2023]
Abstract
We report on the reactive scattering of methyl iodide, CH3I, with atomic oxygen anions O-. This radical ion-molecule reaction can produce different ionic products depending on the angle of attack of the nucleophile O- on the target molecule. We present results on the backside and frontside attack of O- on CH3I, which can lead to I- and IO- products, respectively. We combine crossed-beam velocity map imaging with quantum chemical calculations to unravel the chemical reaction dynamics. Energy-dependent scattering experiments in the range of 0.3-2.0 eV relative collision energy revealed that three different reaction pathways can lead to I- products, making it the predominant observed product. Backside attack occurs via a hydrogen-bonded complex with observed indirect, forward, and sideways scattered iodide products. Halide abstraction via frontside attack produces IO-, which mainly shows isotropic and backward scattered products at low energies. IO- is observed to dissociate further to I- + O at a certain energy threshold and favors more direct dynamics at higher collision energies.
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Affiliation(s)
- Atilay Ayasli
- Institut für Ionenphysik und Angewandte Physik, Universität Innsbruck, Technikerstrasse 25/3, 6020 Innsbruck, Austria
| | - Arnab Khan
- Institut für Ionenphysik und Angewandte Physik, Universität Innsbruck, Technikerstrasse 25/3, 6020 Innsbruck, Austria
| | - Tim Michaelsen
- Institut für Ionenphysik und Angewandte Physik, Universität Innsbruck, Technikerstrasse 25/3, 6020 Innsbruck, Austria
| | - Thomas Gstir
- Institut für Ionenphysik und Angewandte Physik, Universität Innsbruck, Technikerstrasse 25/3, 6020 Innsbruck, Austria
| | - Milan Ončák
- Institut für Ionenphysik und Angewandte Physik, Universität Innsbruck, Technikerstrasse 25/3, 6020 Innsbruck, Austria
| | - Roland Wester
- Institut für Ionenphysik und Angewandte Physik, Universität Innsbruck, Technikerstrasse 25/3, 6020 Innsbruck, Austria
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2
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Plamper D, Fujioka K, Schmidt S, Sun R, Weitzel KM. Ion-molecule reactions in the HBr + + HCl (DCl) system: a combined experimental and theoretical study. Phys Chem Chem Phys 2023; 25:2629-2640. [PMID: 36602406 DOI: 10.1039/d2cp03654a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Reactions in the system HBr+ + HCl (DCl) were investigated inside a guided ion-beam apparatus under single-collision conditions. In the HBr+ + HCl system, the proton transfer (PTHCl) and charge transfer (CT) are observable. In the HBr+ + DCl system, proton transfer (PTDCl) and deuterium abstraction (DA) are accessible. The cross sections for all reaction channels were measured as a function of the collision energy Ecm and of the rotational energy Erot of the ion. The rotationally state-selective formation of the ionic species was realized by resonance-enhanced multiphoton ionization (REMPI). As expected, the PT-channels are exothermic, and the cross section decreases with increasing collision energy for both PTHCl and PTDCl. The cross section for DA also decreases with an increasing Ec.m.. In the case of a considerably endothermic CT-channel, the reaction efficiency increases with increasing collision energy but has an overall much smaller cross sections compared to PT and DA reactions. Both PT-reactions are hindered by ion rotation, whereas DA is independent of Erot. The CT-channel shows a rotational enhancement near the thermochemical threshold. The experiment is complemented by theory, using ab initio molecular dynamics (AIMD, also known as direct dynamics) simulations and taking the rotational enhancement of HBr+ into account. The simulations show good agreement with the experimental results. The cross section of PTHCl decreases with an increase of the rotational energy. Furthermore, the absolute cross sections are in the same order of magnitude. The CT channel shows no reactions in the simulation.
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Affiliation(s)
- Dominik Plamper
- Philipps-Universität Marburg, Fachbereich Chemie, 35032 Marburg, Germany.
| | - Kazuumi Fujioka
- Department of Chemistry, University of Hawai'i at Manoa, Honolulu, Hawaii 96822, USA.
| | - Sebastian Schmidt
- Philipps-Universität Marburg, Fachbereich Chemie, 35032 Marburg, Germany.
| | - Rui Sun
- Department of Chemistry, University of Hawai'i at Manoa, Honolulu, Hawaii 96822, USA.
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3
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Song K, Song H, Li J. Validating experiments for the reaction H 2 + NH 2- by dynamical calculations on an accurate full-dimensional potential energy surface. Phys Chem Chem Phys 2022; 24:10160-10167. [PMID: 35420091 DOI: 10.1039/d2cp00870j] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Ion-molecule reactions play key roles in the field of ion related chemistry. As a prototypical multi-channel ion-molecule reaction, the reaction H2 + NH2- → NH3 + H- has been studied for decades. In this work, we develop a new globally accurate potential energy surface (PES) for the title system based on hundreds of thousands of sampled points over a wide dynamically relevant region that covers long-range interacting configuration space. The permutational invariant polynomial-neural network (PIP-NN) method is used for fitting and the resulting total root mean squared error (RMSE) is extremely small, 0.026 kcal mol-1. Extensive dynamical and kinetic calculations are carried out on this PIP-NN PES. Impressively, a unique phenomenon of significant reactivity suppression by exciting the rotational mode of H2 is reported, supported by both the quasi-classical trajectory (QCT) and quantum dynamics (QD) calculations. Further analysis uncovers that exciting the H2 rotational mode would prevent the formation of the reactant complex and thus suppress the reactivity. The calculated rate coefficients for H2/D2 + NH2- agree well with the experimental results, which show an inverse temperature dependence from 50 to 300 K, consistent with the capture nature of this barrierless reaction. The significant kinetic isotope effect observed by experiments is well reproduced by the QCT computations as well.
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Affiliation(s)
- Kaisheng Song
- School of Chemistry and Chemical Engineering & Chongqing Key Laboratory of Theoretical and Computational Chemistry, Chongqing University, Chongqing 401331, P. R. China.
| | - Hongwei Song
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan 430071, China.
| | - Jun Li
- School of Chemistry and Chemical Engineering & Chongqing Key Laboratory of Theoretical and Computational Chemistry, Chongqing University, Chongqing 401331, P. R. China.
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4
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Zhu Y, Li R, Song H. Kinetic and dynamic studies of the NH 2+ + H 2 reaction on a high-level ab initio potential energy surface. Phys Chem Chem Phys 2022; 24:25663-25672. [DOI: 10.1039/d2cp03859e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The dynamics and kinetics of the NH2+ + H2 reaction are investigated on a newly developed ab initio potential energy surface using the quasi-classical trajectory method.
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Affiliation(s)
- Yongfa Zhu
- School of Chemistry and Chemical Engineering, Hubei Polytechnic University, Huangshi 435003, China
| | - Rui Li
- School of Chemistry and Chemical Engineering, Hubei Polytechnic University, Huangshi 435003, China
| | - Hongwei Song
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan 430071, China
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5
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Pan M, Xiang H, Li Y, Song H. Study on the kinetics and dynamics of the H 2 + NH 2- reaction on a high-level ab initio potential energy surface. Phys Chem Chem Phys 2021; 23:17848-17855. [PMID: 34612274 DOI: 10.1039/d1cp02423j] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Gas-phase ion-molecule reactions play major roles in many fields of chemistry and physics. The reaction of an amino radical anion with a hydrogen molecule is one of the simplest proton transfer reactions involving anions. A globally accurate full-dimensional potential energy surface (PES) for the NH2- + H2 reaction is developed by the fundamental invariant-neural network method, resulting in a root mean square error of 0.116 kcal mol-1. Quasi-classical trajectory calculations are then carried out on the newly developed PES to give integral cross sections, differential cross sections and thermal rate coefficients. This reaction has two reaction channels, proton transfer and hydrogen exchange. The reactivity of the proton transfer channel is about one or two orders of magnitude stronger than that of the hydrogen exchange channel in the energy range studied. Vibrational excitation of H2 promotes the proton transfer reaction, while fundamental excitation of each vibrational mode of NH2- has a negligible effect. In addition, the theoretical rate coefficients of the proton transfer reaction on the PES show inverse temperature dependence from 150 to 750 K, in accordance with the available experimental results.
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Affiliation(s)
- Mengyi Pan
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan 430071, China.
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6
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Wester R. Fifty years of nucleophilic substitution in the gas phase. MASS SPECTROMETRY REVIEWS 2021; 41:627-644. [PMID: 34060119 PMCID: PMC9291629 DOI: 10.1002/mas.21705] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 05/05/2021] [Accepted: 05/05/2021] [Indexed: 06/12/2023]
Abstract
Bimolecular nucleophilic substitution ( S N 2 ) reactions have become a model system for the investigation of structure-reactivity relationships, stereochemistry, solvent influences, and detailed atomistic dynamics. In this review, the progress during five decades of experimental and theoretical research on gas phase S N 2 reactions is discussed. Many advancements of the employed methods have led to a tremendous increase in our understanding of the properties and the dynamics of these reactions. For reactions involving six atoms a quantitative agreement of the differential reactive scattering cross sections has already been achieved, in the future it is expected that even larger polyatomic reactions systems become tractable. Furthermore, studies with higher precision, improved reactant control, and a more accurate theoretical treatment of quantum effects are envisioned.
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Affiliation(s)
- Roland Wester
- Institut für Ionenphysik und Angewandte PhysikUniversität InnsbruckTechnikerstraße 256020 InnsbruckAustria
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7
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Zhu Y, Tian L, Song H, Yang M. Kinetic and dynamic studies of the H3++ CO → H2+ HCO+/HOC+reaction on a high-levelab initiopotential energy surface. J Chem Phys 2019. [DOI: 10.1063/1.5110934] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Yongfa Zhu
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Li Tian
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China
- College of Physical Science and Technology, Huazhong Normal University, Wuhan 430079, China
| | - Hongwei Song
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China
| | - Minghui Yang
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China
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8
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Vallance C. Multi-mass velocity-map imaging studies of photoinduced and electron-induced chemistry. Chem Commun (Camb) 2019; 55:6336-6352. [PMID: 31099379 DOI: 10.1039/c9cc02426c] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Multi-mass velocity-map imaging (VMI) is becoming established as a promising method for probing the dynamics of a variety of gas-phase chemical processes. We provide an overview of velocity-map imaging and multi-mass velocity-map imaging techniques, highlighting examples in which these approaches have been used to provide mechanistic insights into a range of photoinduced and electron-induced chemical processes. Multi-mass detection capabilities have also led to the development of two new tools for the chemical dynamics toolbox, in the form of Coulomb-explosion imaging and covariance-map imaging. These allow details of molecular structure to be followed in real time over the course of a chemical reaction, offering the tantalising prospect of recording real-time 'molecular movies' of chemical dynamics. As these new methods become established within the reaction dynamics community, they promise new mechanistic insights into chemistry relevant to fields ranging from atmospheric chemistry and astrochemistry through to synthetic organic photochemistry and biology.
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Affiliation(s)
- Claire Vallance
- Department of Chemistry, University of Oxford, Chemistry Research Laboratory, 12 Mansfield Rd, Oxford OX1 3TA, UK.
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9
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Yu F. Dynamic exit-channel pathways of the microsolvated HOO -(H 2O) + CH 3Cl S N2 reaction: Reaction mechanisms at the atomic level from direct chemical dynamics simulations. J Chem Phys 2018; 148:014302. [PMID: 29306291 DOI: 10.1063/1.5000400] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Microsolvated bimolecular nucleophilic substitution (SN2) reaction of monohydrated hydrogen peroxide anion [HOO-(H2O)] with methyl chloride (CH3Cl) has been investigated with direct chemical dynamics simulations at the M06-2X/6-31+G(d,p) level of theory. Dynamic exit-channel pathways and corresponding reaction mechanisms at the atomic level are revealed in detail. Accordingly, a product distribution of 0.85:0.15 is obtained for Cl-:Cl-(H2O), which is consistent with a previous experiment [D. L. Thomsen et al. J. Am. Chem. Soc. 135, 15508 (2013)]. Compared with the HOO- + CH3Cl SN2 reaction, indirect dynamic reaction mechanisms are enhanced by microsolvation for the HOO-(H2O) + CH3Cl SN2 reaction. On the basis of our simulations, further crossed molecular beam imaging experiments are highly suggested for the SN2 reactions of HOO- + CH3Cl and HOO-(H2O) + CH3Cl.
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Affiliation(s)
- Feng Yu
- Department of Physics, School of Science, Xi'an Technological University, No. 4 Jinhua North Road, Xi'an, Shaanxi 710032, China
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10
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Teiwes R, Elm J, Handrup K, Jensen EP, Bilde M, Pedersen HB. Atmospheric chemistry of iodine anions: elementary reactions of I−, IO−, and IO2− with ozone studied in the gas-phase at 300 K using an ion trap. Phys Chem Chem Phys 2018; 20:28606-28615. [DOI: 10.1039/c8cp05721d] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Using a radio-frequency ion trap to study ion–molecule reactions under isolated conditions, we report a direct experimental determination of reaction rate constants for the sequential oxidation of iodine anions by ozone at room temperature (300 K).
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Affiliation(s)
- Ricky Teiwes
- Department of Physics and Astronomy, Aarhus University, DK-8000 Aarhus C, Denmark
| | - Jonas Elm
- Department of Chemistry, Aarhus University, DK-8000 Aarhus C, Denmark
| | - Karsten Handrup
- Department of Physics and Astronomy, Aarhus University, DK-8000 Aarhus C, Denmark
| | - Ellen P. Jensen
- Department of Physics and Astronomy, Aarhus University, DK-8000 Aarhus C, Denmark
| | - Merete Bilde
- Department of Chemistry, Aarhus University, DK-8000 Aarhus C, Denmark
| | - Henrik B. Pedersen
- Department of Physics and Astronomy, Aarhus University, DK-8000 Aarhus C, Denmark
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11
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Bop CT, Trabelsi T, Hammami K, Mogren Al Mogren M, Lique F, Hochlaf M. Cold collisions of SH− with He: Potential energy surface and rate coefficients. J Chem Phys 2017; 147:124301. [DOI: 10.1063/1.4994970] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- C. T. Bop
- Laboratory of Atoms Lasers, Department of Physics, Faculty of Sciences and Techniques, University Cheikh Anta Diop of Dakar, Dakar, Senegal
| | - T. Trabelsi
- Laboratory of Atomic Molecular Spectroscopy and Applications, Department of Physics, Faculty of Sciences, University Tunis El Manar, Campus Universities, 1060 Tunis, Tunisia
| | - K. Hammami
- Laboratory of Atomic Molecular Spectroscopy and Applications, Department of Physics, Faculty of Sciences, University Tunis El Manar, Campus Universities, 1060 Tunis, Tunisia
| | - M. Mogren Al Mogren
- Chemistry Department, Faculty of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Kingdom of Saudi Arabia
| | - F. Lique
- LOMC-UMR 6294, CNRS-Université du Havre, 25 Rue Philippe Lebon, BP 1123, 76 063 Le Havre Cedex, France
| | - M. Hochlaf
- Université Paris-Est, Laboratoire Modélisation et Simulation Multi Echelle, MSME UMR 8208 CNRS, 5 Blvd. Descartes, F-77454 Marne-la-Vallée, France
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12
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Affiliation(s)
- Jennifer Meyer
- Institut für Ionenphysik und Angewandte Physik, Universität Innsbruck, 6020 Innsbruck, Austria
| | - Roland Wester
- Institut für Ionenphysik und Angewandte Physik, Universität Innsbruck, 6020 Innsbruck, Austria
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13
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Affiliation(s)
| | - Catherine Walsh
- Leiden
Observatory, Leiden University, P.O. Box 9513, 2300 RA Leiden, The Netherlands
- School
of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, U.K
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14
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Tomza M. Cold interactions and chemical reactions of linear polyatomic anions with alkali-metal and alkaline-earth-metal atoms. Phys Chem Chem Phys 2017; 19:16512-16523. [DOI: 10.1039/c7cp02127e] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Cold interactions and channels of chemical reactions between linear polyatomic anions and atoms are investigated, opening the way for sympathetic cooling and controlled chemistry in these systems.
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Affiliation(s)
- Michał Tomza
- Centre of New Technologies
- University of Warsaw
- 02-097 Warsaw
- Poland
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15
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Carrascosa E, Meyer J, Wester R. Imaging the dynamics of ion–molecule reactions. Chem Soc Rev 2017; 46:7498-7516. [DOI: 10.1039/c7cs00623c] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A range of ion–molecule reactions have been studied in the last years using the crossed-beam ion imaging technique, from charge transfer and proton transfer to nucleophilic substitution and elimination.
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Affiliation(s)
- Eduardo Carrascosa
- Institut für Ionenphysik und Angewandte Physik
- Universität Innsbruck
- 6020 Innsbruck
- Austria
| | - Jennifer Meyer
- Institut für Ionenphysik und Angewandte Physik
- Universität Innsbruck
- 6020 Innsbruck
- Austria
| | - Roland Wester
- Institut für Ionenphysik und Angewandte Physik
- Universität Innsbruck
- 6020 Innsbruck
- Austria
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16
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Wang Y, Song H, Szabó I, Czakó G, Guo H, Yang M. Mode-Specific SN2 Reaction Dynamics. J Phys Chem Lett 2016; 7:3322-3327. [PMID: 27505286 DOI: 10.1021/acs.jpclett.6b01457] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Despite its importance in chemistry, the microscopic dynamics of bimolecular nucleophilic substitution (SN2) reactions is still not completely elucidated. In this publication, the dynamics of a prototypical SN2 reaction (F(-) + CH3Cl → CH3F + Cl(-)) is investigated using a high-dimensional quantum mechanical model on an accurate potential energy surface (PES) and further analyzed by quasi-classical trajectories on the same PES. While the indirect mechanism dominates at low collision energies, the direct mechanism makes a significant contribution. The reactivity is found to depend on the specific reactant vibrational mode excitation. The mode specificity, which is more prevalent in the direct reaction, is rationalized by a transition-state-based model.
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Affiliation(s)
- Yan Wang
- Key Laboratory of Magnetic Resonance in Biological Systems, National Center for Magnetic Resonance in Wuhan, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences , Wuhan 430071, China
- School of Chemical and Environmental Engineering, Hubei University for Nationalities , Enshi 445000, China
| | - Hongwei Song
- Key Laboratory of Magnetic Resonance in Biological Systems, National Center for Magnetic Resonance in Wuhan, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences , Wuhan 430071, China
| | - István Szabó
- Department of Physical Chemistry and Materials Science, Institute of Chemistry, University of Szeged , Rerrich Béla tér 1, Szeged H-6720, Hungary
| | - Gábor Czakó
- Department of Physical Chemistry and Materials Science, Institute of Chemistry, University of Szeged , Rerrich Béla tér 1, Szeged H-6720, Hungary
| | - Hua Guo
- Department of Chemistry and Chemical Biology, University of New Mexico , Albuquerque, New Mexico 87131, United States
| | - Minghui Yang
- Key Laboratory of Magnetic Resonance in Biological Systems, National Center for Magnetic Resonance in Wuhan, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences , Wuhan 430071, China
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17
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Akhgarnusch A, Tang WK, Zhang H, Siu CK, Beyer MK. Charge transfer reactions between gas-phase hydrated electrons, molecular oxygen and carbon dioxide at temperatures of 80-300 K. Phys Chem Chem Phys 2016; 18:23528-37. [PMID: 27498686 DOI: 10.1039/c6cp03324e] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The recombination reactions of gas-phase hydrated electrons (H2O)n˙(-) with CO2 and O2, as well as the charge exchange reaction of CO2˙(-)(H2O)n with O2, were studied by Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometry in the temperature range T = 80-300 K. Comparison of the rate constants with collision models shows that CO2 reacts with 50% collision efficiency, while O2 reacts considerably slower. Nanocalorimetry yields internally consistent results for the three reactions. Converted to room temperature condensed phase, this yields hydration enthalpies of CO2˙(-) and O2˙(-), ΔHhyd(CO2˙(-)) = -334 ± 44 kJ mol(-1) and ΔHhyd(O2˙(-)) = -404 ± 28 kJ mol(-1). Quantum chemical calculations show that the charge exchange reaction proceeds via a CO4˙(-) intermediate, which is consistent with a fully ergodic reaction and also with the small efficiency. Ab initio molecular dynamics simulations corroborate this picture and indicate that the CO4˙(-) intermediate has a lifetime significantly above the ps regime.
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Affiliation(s)
- Amou Akhgarnusch
- Institut für Physikalische Chemie, Christian-Albrechts-Universität zu Kiel, Olshausenstrasse 40, 24098 Kiel, Germany
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18
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Höltkemeier B, Weckesser P, López-Carrera H, Weidemüller M. Buffer-Gas Cooling of a Single Ion in a Multipole Radio Frequency Trap Beyond the Critical Mass Ratio. PHYSICAL REVIEW LETTERS 2016; 116:233003. [PMID: 27341228 DOI: 10.1103/physrevlett.116.233003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2015] [Indexed: 06/06/2023]
Abstract
We theoretically investigate the dynamics of a trapped ion immersed in a spatially localized buffer gas. For a homogeneous buffer gas, the ion's energy distribution reaches a stable equilibrium only if the mass of the buffer gas atoms is below a critical value. This limitation can be overcome by using multipole traps in combination with a spatially confined buffer gas. Using a generalized model for elastic collisions of the ion with the buffer-gas atoms, the ion's energy distribution is numerically determined for arbitrary buffer-gas distributions and trap parameters. Three regimes characterized by the respective analytic form of the ion's equilibrium energy distribution are found. Final ion temperatures down to the millikelvin regime can be achieved by adiabatically decreasing the spatial extension of the buffer gas and the effective ion trap depth (forced sympathetic cooling).
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Affiliation(s)
- Bastian Höltkemeier
- Physikalisches Institut, Ruprecht-Karls-Universität Heidelberg, INF 226, 69120 Heidelberg, Germany
| | - Pascal Weckesser
- Physikalisches Institut, Ruprecht-Karls-Universität Heidelberg, INF 226, 69120 Heidelberg, Germany
| | - Henry López-Carrera
- Physikalisches Institut, Ruprecht-Karls-Universität Heidelberg, INF 226, 69120 Heidelberg, Germany
| | - Matthias Weidemüller
- Physikalisches Institut, Ruprecht-Karls-Universität Heidelberg, INF 226, 69120 Heidelberg, Germany
- Hefei National Laboratory for Physical Sciences at the Microscale and Department of Modern Physics, and CAS Center for Excellence and Synergetic Innovation Center in Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
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19
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Zhang J, Yang L, Sheng L. Electronic Structure Theory Study of the Microsolvated F(-)(H2O) + CH3I SN2 Reaction. J Phys Chem A 2016; 120:3613-22. [PMID: 27126610 DOI: 10.1021/acs.jpca.6b00726] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The potential energy profile of microhydrated fluorine ion reaction with methyl iodine has been characterized by extensive electronic structure calculations. Both hydrogen-bonded F(-)(H2O)---HCH2I and ion-dipole F(-)(H2O)---CH3I complexes are formed for the reaction entrance and the PES in vicinity of these complexes is very flat, which may have important implications for the reaction dynamics. The water molecule remains on the fluorine side until the reactive system goes to the SN2 saddle point. It can easily move to the iodine side with little barrier, but in a nonsynchronous reaction path after the dynamical bottleneck to the reaction, which supports the previous prediction for microsolvated SN2 systems. The influence of solvating water molecule on the reaction mechanism is probed by comparing with the influence of the nonsolvated analogue and other microsolvated SN2 systems. Taking the CCSD(T) single-point calculations based on MP2-optimized geometries as benchmark, the DFT functionals B97-1 and B3LYP are found to better characterize the potential energy profile for the title reaction and are recommended as the preferred methods for the direct dynamics simulations to uncover the dynamic behaviors.
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Affiliation(s)
- Jiaxu Zhang
- School of Chemistry and Chemical Engineering, Harbin Institute of Technology , Harbin 150001, P. R. China
| | - Li Yang
- School of Chemistry and Chemical Engineering, Harbin Institute of Technology , Harbin 150001, P. R. China
| | - Li Sheng
- School of Chemistry and Chemical Engineering, Harbin Institute of Technology , Harbin 150001, P. R. China
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20
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Liu X, Zhang J, Yang L, Sun R. Theoretical Studies on F(-) + NH2Cl Reaction: Nucleophilic Substitution at Neutral Nitrogen. J Phys Chem A 2016; 120:3740-6. [PMID: 27144809 DOI: 10.1021/acs.jpca.6b03487] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The SN2 reactions at N center, denoted as SN2@N, has been recognized to play a significant role in carcinogenesis, although they are less studied and less understood. The potential energy profile for the model reaction of SN2@N, chloramine (NH2Cl) with fluorine anion (F(-)), has been characterized by extensive electronic structure calculations. The back-side SN2 channel dominates the reaction with the front-side SN2 channel becoming feasible at higher energies. The minimum energy pathway shows a resemblance to the well-known double-well potential model for SN2 reactions at carbon. However, the complexes involving nitrogen on both sides of the reaction barrier are characterized by NH---X (X = F or Cl) hydrogen bond and possess C1 symmetry, in contrast to the more symmetric ion-dipole carbon analogues. In the F(-) + NH2Cl system, the proton transfer pathway is found to become more competitive with the SN2 pathway than in the F(-) + CH3Cl system. The calculations reported here indicate that stationary point properties on the F(-) + NH2Cl potential energy surface are slightly perturbed by the theories employed. The MP2 and CAM-B3LYP, as well as M06-2X and MPW1K functionals give overall best agreement with the benchmark CCSD(T)/CBS energies for the major SN2 reaction channel, and are recommended as the preferred methods for the direct dynamics simulations to uncover the dynamic behaviors of the title reaction.
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Affiliation(s)
- Xu Liu
- School of Chemistry and Chemical Engineering Harbin Institute of Technology Harbin 150001, P. R. China
| | - Jiaxu Zhang
- School of Chemistry and Chemical Engineering Harbin Institute of Technology Harbin 150001, P. R. China
| | - Li Yang
- School of Chemistry and Chemical Engineering Harbin Institute of Technology Harbin 150001, P. R. China
| | - Rui Sun
- Department of Chemistry University of Chicago Chicago, Illinois 60637, United States
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21
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Yu F. Dynamic Reaction Mechanisms of ClO(-) with CH3Cl: Comparison Between Direct Dynamics Trajectory Simulations and Experiment. J Phys Chem A 2016; 120:1813-8. [PMID: 26928354 DOI: 10.1021/acs.jpca.5b12664] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We have investigated the dynamic reaction mechanisms of *ClO¯ with CH3Cl (the asterisk is utilized to label a different Cl atom). Ab initio molecular dynamics simulations at the MP2/6-31+G(d,p) level of theory have been employed to compute the dynamic trajectories. On the basis of our simulations, the dynamic reaction pathways for the bimolecular nucleophilic substitution (SN2) reaction channel and SN2-induced elimination reaction channel are clearly illustrated. For the SN2 reaction channel, some trajectories directly dissociate to the final products of CH3O*Cl and Cl¯, whereas the others involve the dynamic Cl¯···CH3O*Cl intermediate complex. As to the SN2-induced elimination reaction channel, the trajectories lead to the final products of CH2O, HCl, and *Cl¯ through the dynamic Cl¯···CH3O*Cl intermediate complex. More significantly, the product branching ratios of Cl¯ and *Cl¯ predicted by our simulations are basically consistent with previous experimental results (Villano et al. J. Am. Chem. Soc. 2009, 131, 8227-8233).
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Affiliation(s)
- Feng Yu
- Department of Physics, School of Science, Xi'an Technological University , No. 4 Jinhua North Road, Xi'an, Shaanxi 710032, China
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22
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Zhang J, Xie J, Hase WL. Dynamics of the F– + CH3I → HF + CH2I– Proton Transfer Reaction. J Phys Chem A 2015; 119:12517-25. [DOI: 10.1021/acs.jpca.5b08167] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Jiaxu Zhang
- Institute
of Theoretical and Simulation Chemistry, Academy of Fundamental and
Interdisciplinary Sciences, Harbin Institute of Technology, Harbin 150080, P. R. China
| | - Jing Xie
- Department
of Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - William L. Hase
- Department
of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas 79409, United States
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23
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Cooper GA, Kartouzian A, Gentleman AS, Iskra A, van Wijk R, Mackenzie SR. Dissociation energies of Ag–RG (RG = Ar, Kr, Xe) and AgO molecules from velocity map imaging studies. J Chem Phys 2015; 143:124302. [DOI: 10.1063/1.4931486] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Graham A. Cooper
- Physical and Theoretical Chemistry Laboratory, Oxford Chemistry, South Parks Road, Oxford OX1 3QZ, United Kingdom
| | - Aras Kartouzian
- Physical and Theoretical Chemistry Laboratory, Oxford Chemistry, South Parks Road, Oxford OX1 3QZ, United Kingdom
- Department of Physical Chemistry, Catalysis Research Center, Technische Universität München, Lichtenbergstr. 4, 85748 Garching, Germany
| | - Alexander S. Gentleman
- Physical and Theoretical Chemistry Laboratory, Oxford Chemistry, South Parks Road, Oxford OX1 3QZ, United Kingdom
| | - Andreas Iskra
- Physical and Theoretical Chemistry Laboratory, Oxford Chemistry, South Parks Road, Oxford OX1 3QZ, United Kingdom
| | - Robert van Wijk
- Physical and Theoretical Chemistry Laboratory, Oxford Chemistry, South Parks Road, Oxford OX1 3QZ, United Kingdom
| | - Stuart R. Mackenzie
- Physical and Theoretical Chemistry Laboratory, Oxford Chemistry, South Parks Road, Oxford OX1 3QZ, United Kingdom
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24
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Akhgarnusch A, Höckendorf RF, Beyer MK. Thermochemistry of the Reaction of SF6 with Gas-Phase Hydrated Electrons: A Benchmark for Nanocalorimetry. J Phys Chem A 2015; 119:9978-85. [PMID: 26356833 DOI: 10.1021/acs.jpca.5b06975] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The reaction of sulfur hexafluoride with gas-phase hydrated electrons (H2O)n(-), n ≈ 60-130, is investigated at temperatures T = 140-300 K by Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometry. SF6 reacts with a temperature-independent rate of 3.0 ± 1.0 × 10(-10) cm(3) s(-1) via exclusive formation of the hydrated F(-) anion and the SF5(•) radical, which evaporates from the cluster. Nanocalorimetry yields a reaction enthalpy of ΔHR,298K = 234 ± 24 kJ mol(-1). Combined with literature thermochemical data from bulk aqueous solution, these result in an F5S-F bond dissociation enthalpy of ΔH298K = 455 ± 24 kJ mol(-1), in excellent agreement with all high-level quantum chemical calculations in the literature. A combination with gas-phase literature thermochemistry also yields an experimental value for the electron affinity of SF5(•), EA(SF5(•)) = 4.27 ± 0.25 eV.
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Affiliation(s)
- Amou Akhgarnusch
- Institut für Physikalische Chemie, Christian-Albrechts-Universität zu Kiel , Olshausenstrasse 40, 24098 Kiel, Germany.,Institut für Ionenphysik und Angewandte Physik, Leopold-Franzens-Universität Innsbruck , Technikerstrasse 25, 6020 Innsbruck, Austria
| | - Robert F Höckendorf
- Institut für Physikalische Chemie, Christian-Albrechts-Universität zu Kiel , Olshausenstrasse 40, 24098 Kiel, Germany
| | - Martin K Beyer
- Institut für Physikalische Chemie, Christian-Albrechts-Universität zu Kiel , Olshausenstrasse 40, 24098 Kiel, Germany.,Institut für Ionenphysik und Angewandte Physik, Leopold-Franzens-Universität Innsbruck , Technikerstrasse 25, 6020 Innsbruck, Austria
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25
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Hennig C, Schmatz S. Mechanisms of SN2 reactions: insights from a nearside/farside analysis. Phys Chem Chem Phys 2015; 17:26670-6. [DOI: 10.1039/c5cp04312c] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A nearside/farside analysis, performed for the first time for a complex-forming polyatomic reaction, reveals details of the reaction mechanism.
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Affiliation(s)
- Carsten Hennig
- Institut für Physikalische Chemie
- Universität Göttingen
- D-37077 Göttingen
- Germany
| | - Stefan Schmatz
- Institut für Physikalische Chemie
- Universität Göttingen
- D-37077 Göttingen
- Germany
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26
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Kowalewski M, Mikosch J, Wester R, de Vivie-Riedle R. Nucleophilic Substitution Dynamics: Comparing Wave Packet Calculations with Experiment. J Phys Chem A 2014; 118:4661-9. [DOI: 10.1021/jp503974u] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- M. Kowalewski
- Department
of Chemistry, Ludwig-Maximilians-Universität, D-81377 Munich, Germany
- Division
of Scientific Computing, Department of Information Technology, Uppsala University, SE-75105 Uppsala, Sweden
| | - J. Mikosch
- Max-Born-Institute, Max-Born-Strasse 2A, D-12489 Berlin, Germany
| | - R. Wester
- Institut
für Ionenphysik und Angewandte Physik, Universität Innsbruck, Technikerstraße 25/3, 6020 Innsbruck, Austria
| | - R. de Vivie-Riedle
- Department
of Chemistry, Ludwig-Maximilians-Universität, D-81377 Munich, Germany
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27
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Stei M, von Vangerow J, Otto R, Kelkar AH, Carrascosa E, Best T, Wester R. High resolution spatial map imaging of a gaseous target. J Chem Phys 2013; 138:214201. [DOI: 10.1063/1.4807482] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
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28
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Ayouz M, Dulieu O, Robert J. Resonant States of the H3– Molecule and Its Isotopologues D2H– and H2D–. J Phys Chem A 2013; 117:9941-9. [DOI: 10.1021/jp4000279] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- M. Ayouz
- Laboratoire
de Génie des Procédés et Matériaux, Ecole Centrale de Paris, Bât. Dumas, 92295 Châtenay-Malabry
Cedex, France
| | - O. Dulieu
- Laboratoire
Aimé Cotton, CNRS/Univ Paris-Sud/ENS Cachan, Bât. 505, Campus d’Orsay, 91405 Orsay Cedex, France
| | - J. Robert
- Laboratoire
Aimé Cotton, CNRS/Univ Paris-Sud/ENS Cachan, Bât. 505, Campus d’Orsay, 91405 Orsay Cedex, France
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29
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Xie J, Sun R, Siebert MR, Otto R, Wester R, Hase WL. Direct Dynamics Simulations of the Product Channels and Atomistic Mechanisms for the OH– + CH3I Reaction. Comparison with Experiment. J Phys Chem A 2013; 117:7162-78. [DOI: 10.1021/jp4008027] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Jing Xie
- Department of Chemistry
and Biochemistry, Texas Tech University, Lubbock, Texas 79409-1061, United States
| | - Rui Sun
- Department of Chemistry
and Biochemistry, Texas Tech University, Lubbock, Texas 79409-1061, United States
| | - Matthew R. Siebert
- Department of Chemistry, Missouri State University, Springfield,
Missouri 65897, United States
| | - Rico Otto
- Institut fur Ionenphysik und Angewandte
Physik, Universität Innsbruck, Technikerstraße
25/3, A-6020 Innsbruck, Austria
| | - Roland Wester
- Institut fur Ionenphysik und Angewandte
Physik, Universität Innsbruck, Technikerstraße
25/3, A-6020 Innsbruck, Austria
| | - William L. Hase
- Department of Chemistry
and Biochemistry, Texas Tech University, Lubbock, Texas 79409-1061, United States
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30
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Mikosch J, Zhang J, Trippel S, Eichhorn C, Otto R, Sun R, de Jong WA, Weidemüller M, Hase WL, Wester R. Indirect dynamics in a highly exoergic substitution reaction. J Am Chem Soc 2013; 135:4250-9. [PMID: 23324058 DOI: 10.1021/ja308042v] [Citation(s) in RCA: 85] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The highly exoergic nucleophilic substitution reaction F(-) + CH3I shows reaction dynamics strikingly different from that of substitution reactions of larger halogen anions. Over a wide range of collision energies, a large fraction of indirect scattering via a long-lived hydrogen-bonded complex is found both in crossed-beam imaging experiments and in direct chemical dynamics simulations. Our measured differential scattering cross sections show large-angle scattering and low product velocities for all collision energies, resulting from efficient transfer of the collision energy to internal energy of the CH3F reaction product. Both findings are in strong contrast to the previously studied substitution reaction of Cl(-) + CH3I [Science 2008, 319, 183-186] at all but the lowest collision energies, a discrepancy that was not captured in a subsequent study at only a low collision energy [J. Phys. Chem. Lett. 2010, 1, 2747-2752]. Our direct chemical dynamics simulations at the DFT/B97-1 level of theory show that the reaction is dominated by three atomic-level mechanisms, an indirect reaction proceeding via an F(-)-HCH2I hydrogen-bonded complex, a direct rebound, and a direct stripping reaction. The indirect mechanism is found to contribute about one-half of the overall substitution reaction rate at both low and high collision energies. This large fraction of indirect scattering at high collision energy is particularly surprising, because the barrier for the F(-)-HCH2I complex to form products is only 0.10 eV. Overall, experiment and simulation agree very favorably in both the scattering angle and the product internal energy distributions.
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Affiliation(s)
- Jochen Mikosch
- National Research Council of Canada, Ottawa, Ontario K1A 0R6, Canada
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31
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Ayouz M, Mikhailov I, Babikov D, Raoult M, Galtier S, Dulieu O, Kokoouline V. Potential energy and dipole moment surfaces of HCO- for the search of H- in the interstellar medium. J Chem Phys 2012; 136:224310. [PMID: 22713050 DOI: 10.1063/1.4724096] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Potential energy and permanent dipole moment surfaces of the electronic ground state of formyl negative ion HCO(-) are determined for a large number of geometries using the coupled-cluster theory with single and double and perturbative treatment of triple excitations ab initio method with a large basis set. The obtained data are used to construct interpolated surfaces, which are extended analytically to the region of large separations between CO and H(-) with the multipole expansion approach. We have calculated the energy of the lowest rovibrational levels of HCO(-) that should guide the spectroscopic characterization of HCO(-) in laboratory experiments. The study can also help to detect HCO(-) in the cold and dense regions of the interstellar medium where the anion could be formed through the association of abundant CO with still unobserved H(-).
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Affiliation(s)
- M Ayouz
- Department of Chemistry, Marquette University, P.O. Box 1881, Milwaukee, Wisconsin 53201, USA
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32
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Hennig C, Schmatz S. Differential reaction cross sections from rotationally resolved quantum scattering calculations: application to gas-phase SN2 reactions. Phys Chem Chem Phys 2012; 14:12982-91. [PMID: 22903564 DOI: 10.1039/c2cp41141e] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Affiliation(s)
- Carsten Hennig
- Institut für Physikalische Chemie, Universität Göttingen, Tammannstr. 6, D-37077 Göttingen, Germany
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