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Tóth P, Szűcs T, Győri T, Czakó G. Dynamics of the Cl + CH3CN reaction on an automatically-developed full-dimensional ab initio potential energy surface. J Chem Phys 2024; 161:084304. [PMID: 39206830 DOI: 10.1063/5.0220917] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2024] [Accepted: 08/11/2024] [Indexed: 09/04/2024] Open
Abstract
A full-dimensional analytical potential energy surface (PES) is developed for the Cl + CH3CN reaction following our previous work on the benchmark ab initio characterization of the stationary points. The spin-orbit-corrected PES is constructed using the Robosurfer program and a fifth-order permutationally invariant polynomial method for fitting the high-accuracy energy points determined by a ManyHF-based coupled-cluster/triple-zeta-quality composite method. Quasi-classical trajectory simulations are performed at six collision energies between 10 and 60 kcal mol-1. Multiple low-probability product channels are found, including isomerization to isonitrile (CH3NC), but out of the eight possible channels, only the H-abstraction has significant reaction probability; thus, detailed dynamics studies are carried out only for this reaction. The cross sections and opacity functions show that the probability of the H-abstraction reaction increases with increasing collision energy (Ecoll). Scattering angle, initial attack angle, and product relative translational energy distributions indicate that the mechanism changes with the collision energy from indirect/rebound to direct stripping. The distribution of initial attack angles shows a clear preference for methyl group attack but with different angles at different Ecoll values. Post-reaction energy distributions show that the energy transfer is biased toward the products' relative translational energy instead of their internal energy. Rotational and vibrational energy have about the same amount of contribution to the internal energy in the case of both products (HCl and CH2CN), i.e., both of them are formed with high rotational excitations. HCl is produced mostly in the ground vibrational state, while a notable fraction of CH2CN is formed with vibrational excitation.
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Affiliation(s)
- Petra Tóth
- MTA-SZTE Lendület Computational Reaction Dynamics Research Group, Interdisciplinary Excellence Centre and Department of Physical Chemistry and Materials Science, Institute of Chemistry, University of Szeged, Rerrich Béla tér 1, Szeged H-6720, Hungary
| | - Tímea Szűcs
- MTA-SZTE Lendület Computational Reaction Dynamics Research Group, Interdisciplinary Excellence Centre and Department of Physical Chemistry and Materials Science, Institute of Chemistry, University of Szeged, Rerrich Béla tér 1, Szeged H-6720, Hungary
| | - Tibor Győri
- MTA-SZTE Lendület Computational Reaction Dynamics Research Group, Interdisciplinary Excellence Centre and Department of Physical Chemistry and Materials Science, Institute of Chemistry, University of Szeged, Rerrich Béla tér 1, Szeged H-6720, Hungary
| | - Gábor Czakó
- MTA-SZTE Lendület Computational Reaction Dynamics Research Group, Interdisciplinary Excellence Centre and Department of Physical Chemistry and Materials Science, Institute of Chemistry, University of Szeged, Rerrich Béla tér 1, Szeged H-6720, Hungary
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2
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Liu S, Zhang Z, Chen J, Zhang DH. Isotope Effect and Heavy-Light-Heavy Reactivity Oscillation in the Cl + CHD 3/CHT 3 Reaction. J Phys Chem A 2024; 128:1032-1040. [PMID: 38315118 DOI: 10.1021/acs.jpca.3c07348] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2024]
Abstract
Previous experiments and theories have shown the existence of heavy-light-heavy (HLH) reactivity oscillation in the Cl + CH4 reaction and anticipated that similar oscillations should exist in many HLH reactions involving polyatomic reagents. However, the total reaction probabilities for the Cl + CHD3 → HCl + CD3 reaction exhibit only a step-like feature, and the total reaction probabilities for Cl + CHT3 → HCl + CT3 do not show any structure at all. Here, we report seven-dimensional state-to-state quantum dynamics studies for this reaction on the FI-NN PES, and we demonstrate that HLH reactivity oscillations also exist in these two reactions, manifesting as peaks in the reaction probabilities for low product rotational states. These oscillations, however, are obscured in the total reaction probability because of the higher excitation of j ≥ 2 product rotational states. Furthermore, the isotope replacement of nonreactive hydrogen with deuterium and tritium significantly enhances reactivity at collision energies above 0.112 eV, indicating an inverse secondary isotope effect on the probabilities, which is proved to be also caused by HLH mass combination. We also demonstrate that the highly rotational excitation of CHD3 substantially enhances reactivity and the HLH oscillations, similar to HLH triatomic reactions. These observations are completely different from those in the H + CHD3 reaction, which is also a late-barrier reaction. Therefore, the HLH mass combination is very important, which affects not only the reactivity oscillation but also the amplitude and product rotational state distribution and makes the initial rotation excitation play a pivotal role in the reaction.
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Affiliation(s)
- Shu Liu
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning 116023, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhaojun Zhang
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning 116023, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jun Chen
- State Key Laboratory of Structure Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002, China
| | - Dong H Zhang
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning 116023, China
- University of Chinese Academy of Sciences, Beijing 100049, China
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3
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Szűcs T, Czakó G. ManyHF-based full-dimensional potential energy surface development and quasi-classical dynamics for the Cl + CH3NH2 reaction. J Chem Phys 2023; 159:134306. [PMID: 37791624 DOI: 10.1063/5.0166680] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2023] [Accepted: 09/06/2023] [Indexed: 10/05/2023] Open
Abstract
A full-dimensional spin-orbit (SO)-corrected potential energy surface (PES) is developed for the Cl + CH3NH2 multi-channel system. Using the new PES, a comprehensive reaction dynamics investigation is performed for the most reactive hydrogen-abstraction reactions forming HCl + CH2NH2/CH3NH. Hartree-Fock (HF) convergence problems in the reactant region are handled by the ManyHF method, which finds the lowest-energy HF solution considering several different initial guess orbitals. The PES development is carried out with the Robosurfer program package, which iteratively improves the surface. Energy points are computed at the ManyHF-UCCSD(T)-F12a/cc-pVDZ-F12 level of theory combined with basis set (ManyHF-RMP2-F12/cc-pVTZ-F12 - ManyHF-RMP2-F12/cc-pVDZ-F12) and SO (MRCI+Q/aug-cc-pwCVDZ) corrections. Quasi-classical trajectory simulations show that the CH3-side hydrogen abstraction occurs more frequently in contrast to the NH2-side reaction. In both cases, the integral cross sections decrease with increasing collision energy (Ecoll). A reaction mechanism shifting from indirect to direct stripping can be observed from the opacity functions, scattering angle, and translation energy distributions as Ecoll increases. Initial attack angle distributions reveal that chlorine prefers to abstract hydrogen from the approached functional group. The collision-energy dependence of the product energy distributions shows that the initial translational energy mainly transfers to product recoil. The HCl vibrational and rotational energy values are comparable and nearly independent of collision energy, while the CH2NH2 and CH3NH co-products' vibrational energy values are higher than the rotational energy values with more significant Ecoll dependence. The HCl(v = 0) rotational distributions are compared with experiment, setting the direction for future investigations.
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Affiliation(s)
- Tímea Szűcs
- MTA-SZTE Lendület Computational Reaction Dynamics Research Group, Interdisciplinary Excellence Centre and Department of Physical Chemistry and Materials Science, Institute of Chemistry, University of Szeged, Rerrich Béla tér 1, Szeged H-6720, Hungary
| | - Gábor Czakó
- MTA-SZTE Lendület Computational Reaction Dynamics Research Group, Interdisciplinary Excellence Centre and Department of Physical Chemistry and Materials Science, Institute of Chemistry, University of Szeged, Rerrich Béla tér 1, Szeged H-6720, Hungary
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4
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Hoppe H, Manthe U. First-Principles Theory for the Reaction of Chlorine with Methane. J Phys Chem Lett 2022; 13:2563-2566. [PMID: 35285640 DOI: 10.1021/acs.jpclett.2c00407] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
A full-dimensional quantum dynamics simulation of the Cl + CH4 → HCl + CH3 reaction based on first-principles theory is reported. Accurate thermal rate constants are calculated, and perfect agreement with experiment is obtained. Despite the heavy atoms present in both reactants, the passage of the reaction barrier is found to occur within only a few tens of femtoseconds. This surprisingly short time scale results from correlated motion of the transferring hydrogen atom and the hydrogen atoms in the methyl fragment which facilitates irreversible barrier passage without relevant participation of heavy atoms. Resonance effects resulting from the heavy-light-heavy characteristics of the reaction system, which were observed in reactive scattering studies, do not affect the thermal rate constant.
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Affiliation(s)
- Hannes Hoppe
- Theoretische Chemie, Fakultät für Chemie, Universität Bielefeld, Universitätsstr. 25, D-33615 Bielefeld, Germany
| | - Uwe Manthe
- Theoretische Chemie, Fakultät für Chemie, Universität Bielefeld, Universitätsstr. 25, D-33615 Bielefeld, Germany
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5
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Abstract
It has long been predicted that oscillatory behavior exists in reactivity as a function of collision energy for heavy-light-heavy (HLH) chemical reactions in which a light atom is transferred between two heavy atoms or groups of atoms, but direct observation of such a behavior in bimolecular reactions remains a challenge. Here we report a joint theoretical and crossed-molecular-beam study on the Cl + CH4 → HCl + CH3 reaction. A distinctive peak at a collision energy of 0.15 eV for the CH3(v = 0) product was experimentally detected in the backward scattering direction. Detailed quantum-dynamics calculations on a highly accurate potential energy surface revealed that this feature originates from the reactivity oscillation in this HLH polyatomic reaction. We anticipate that such reactivity oscillations exist in many HLH reactions involving polyatomic reagents.
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6
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Czakó G, Győri T, Olasz B, Papp D, Szabó I, Tajti V, Tasi DA. Benchmark ab initio and dynamical characterization of the stationary points of reactive atom + alkane and SN2 potential energy surfaces. Phys Chem Chem Phys 2020; 22:4298-4312. [DOI: 10.1039/c9cp04944d] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We review composite ab initio and dynamical methods and their applications to characterize stationary points of atom/ion + molecule reactions.
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Affiliation(s)
- Gábor Czakó
- MTA-SZTE Lendület Computational Reaction Dynamics Research Group
- Interdisciplinary Excellence Centre and Department of Physical Chemistry and Materials Science
- Institute of Chemistry
- University of Szeged
- Szeged H-6720
| | - Tibor Győri
- MTA-SZTE Lendület Computational Reaction Dynamics Research Group
- Interdisciplinary Excellence Centre and Department of Physical Chemistry and Materials Science
- Institute of Chemistry
- University of Szeged
- Szeged H-6720
| | - Balázs Olasz
- MTA-SZTE Lendület Computational Reaction Dynamics Research Group
- Interdisciplinary Excellence Centre and Department of Physical Chemistry and Materials Science
- Institute of Chemistry
- University of Szeged
- Szeged H-6720
| | - Dóra Papp
- MTA-SZTE Lendület Computational Reaction Dynamics Research Group
- Interdisciplinary Excellence Centre and Department of Physical Chemistry and Materials Science
- Institute of Chemistry
- University of Szeged
- Szeged H-6720
| | - István Szabó
- MTA-SZTE Lendület Computational Reaction Dynamics Research Group
- Interdisciplinary Excellence Centre and Department of Physical Chemistry and Materials Science
- Institute of Chemistry
- University of Szeged
- Szeged H-6720
| | - Viktor Tajti
- MTA-SZTE Lendület Computational Reaction Dynamics Research Group
- Interdisciplinary Excellence Centre and Department of Physical Chemistry and Materials Science
- Institute of Chemistry
- University of Szeged
- Szeged H-6720
| | - Domonkos A. Tasi
- MTA-SZTE Lendület Computational Reaction Dynamics Research Group
- Interdisciplinary Excellence Centre and Department of Physical Chemistry and Materials Science
- Institute of Chemistry
- University of Szeged
- Szeged H-6720
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7
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Houston PL, Nandi A, Bowman JM. A Machine Learning Approach for Prediction of Rate Constants. J Phys Chem Lett 2019; 10:5250-5258. [PMID: 31423788 DOI: 10.1021/acs.jpclett.9b01810] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
We report a machine learning approach to train and predict bimolecular thermal rate constants over a large temperature range. The approach uses Gaussian process (GP) regression to evaluate the difference between accurate quantum results and Eckart-corrected conventional transition state theory, mostly for collinear reactions. Training is done on a database of rate constants for 13 reaction/potential surface combinations, and testing is performed on a set of 39 reaction/potential surface combinations. Averaged over all test reactions, the GP method is within 80% of the accurate answer, whereas transition state theory (TST) is only within 330% and Eckart-corrected TST (ECK) is within 110%. In the tunneling region, GP is generally (with a few exceptions) more accurate and sometimes much more accurate. In the high-temperature recrossing region, GP is significantly more accurate than either TST or ECK, neither of which addresses the possibility of recrossing. The GP predictions for the 3D reactions O(3P) + H2, OH + H2, O(3P) + CH4, and H + CH4, for which accurate quantum results are available, provide further encouragement to the machine learning approach.
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Affiliation(s)
- Paul L Houston
- Department of Chemistry & Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Apurba Nandi
- Department of Chemistry and Cherry L. Emerson Center for Scientic Computation, Emory University, Atlanta, Georgia 30322, United States
| | - Joel M Bowman
- Department of Chemistry and Cherry L. Emerson Center for Scientic Computation, Emory University, Atlanta, Georgia 30322, United States
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8
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Liu C, Kelley CT, Jakubikova E. Molecular Dynamics Simulations on Relaxed Reduced-Dimensional Potential Energy Surfaces. J Phys Chem A 2019; 123:4543-4554. [PMID: 31038956 DOI: 10.1021/acs.jpca.9b02298] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Molecular dynamics (MD) simulations with full-dimensional potential energy surfaces (PESs) obtained from high-level ab initio calculations are frequently used to model reaction dynamics of small molecules (i.e., molecules with up to 10 atoms). Construction of full-dimensional PESs for larger molecules is, however, not feasible since the number of ab initio calculations required grows rapidly with the increase of dimension. Only a small number of coordinates are often essential for describing the reactivity of even very large systems, and reduced-dimensional PESs with these coordinates can be built for reaction dynamics studies. While analytical methods based on transition-state theory framework are well established for analyzing the reduced-dimensional PESs, MD simulation algorithms capable of generating trajectories on such surfaces are more rare. In this work, we present a new MD implementation that utilizes the relaxed reduced-dimensional PES for standard microcanonical (NVE) and canonical (NVT) MD simulations. The method is applied to the pyramidal inversion of a NH3 molecule. The results from the MD simulations on a reduced, three-dimensional PES are validated against the ab initio MD simulations, as well as MD simulations on full-dimensional PES and experimental data.
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9
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Clary DC. Spiers Memorial Lecture : Introductory lecture: quantum dynamics of chemical reactions. Faraday Discuss 2018; 212:9-32. [DOI: 10.1039/c8fd00131f] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This Spiers Memorial Lecture discusses quantum effects that can be calculated and observed in the chemical reactions of small molecules.
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Affiliation(s)
- David C. Clary
- Physical and Theoretical Chemistry Laboratory
- Department of Chemistry
- University of Oxford
- Oxford
- UK
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10
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Karandashev K, Xu ZH, Meuwly M, Vaníček J, Richardson JO. Kinetic isotope effects and how to describe them. STRUCTURAL DYNAMICS (MELVILLE, N.Y.) 2017; 4:061501. [PMID: 29282447 PMCID: PMC5729036 DOI: 10.1063/1.4996339] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2017] [Accepted: 08/23/2017] [Indexed: 06/01/2023]
Abstract
We review several methods for computing kinetic isotope effects in chemical reactions including semiclassical and quantum instanton theory. These methods describe both the quantization of vibrational modes as well as tunneling and are applied to the ⋅H + H2 and ⋅H + CH4 reactions. The absolute rate constants computed with the semiclassical instanton method both using on-the-fly electronic structure calculations and fitted potential-energy surfaces are also compared directly with exact quantum dynamics results. The error inherent in the instanton approximation is found to be relatively small and similar in magnitude to that introduced by using fitted surfaces. The kinetic isotope effect computed by the quantum instanton is even more accurate, and although it is computationally more expensive, the efficiency can be improved by path-integral acceleration techniques. We also test a simple approach for designing potential-energy surfaces for the example of proton transfer in malonaldehyde. The tunneling splittings are computed, and although they are found to deviate from experimental results, the ratio of the splitting to that of an isotopically substituted form is in much better agreement. We discuss the strengths and limitations of the potential-energy surface and based on our findings suggest ways in which it can be improved.
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Affiliation(s)
- Konstantin Karandashev
- Laboratory of Theoretical Physical Chemistry, Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Zhen-Hao Xu
- Department of Chemistry, University of Basel, Klingelbergstrasse 80, CH-4056 Basel, Switzerland
| | - Markus Meuwly
- Department of Chemistry, University of Basel, Klingelbergstrasse 80, CH-4056 Basel, Switzerland
| | - Jiří Vaníček
- Laboratory of Theoretical Physical Chemistry, Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Jeremy O Richardson
- Laboratory of Physical Chemistry, Department of Chemistry and Applied Biosciences, Eidgenössische Technische Hochschule Zürich (ETHZ), CH-8093 Zürich, Switzerland
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11
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Totenhofer AJ, Connor JNL, Nyman G. Angular Scattering Dynamics of the CH4 + Cl → CH3 + HCl Reaction Using Nearside-Farside, Local Angular Momentum, and Resummation Theories. J Phys Chem B 2016; 120:2020-32. [PMID: 26625096 DOI: 10.1021/acs.jpcb.5b10189] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The differential cross section (DCS) for the CH4 + Cl → CH3 + HCl reaction is studied at six total energies where all of the species are in their ground states. The scattering (S) matrix elements have been calculated by the rotating line umbrella method for a dual-level ab initio analytic potential energy surface. We make the first application to this reaction of nearside-farside (NF) and local angular momentum (LAM) techniques, including resummation orders (r) of 0, 1, 2, and 3 for the partial-wave series representation of the full scattering amplitude. We find that resummation usually cleans the NF r = 0 DCSs of unphysical oscillations, especially at small angles. This cleaning effect is typically most pronounced when changing from no resummation (r = 0) to r = 1; further resummations from r = 1 to r = 2 and from r = 2 to r = 3 have smaller effects. The NF DCS analyses show that the reaction is N-dominated at sideward and large angles, whereas at small angles there are oscillations caused by NF interference. The NF LAM analysis provides consistent and complementary information, in particular for the total angular momenta that contribute to the reaction at different scattering angles. The NF analyses also provide justification for simpler N-dominant dynamical theories such as the semiclassical optical model, which provides an explanation for the distorted mirror image effect for the moduli of the S matrix elements and the DCSs, as well as the use of a hard-sphere DCS over limited angular ranges.
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Affiliation(s)
- A J Totenhofer
- School of Chemistry, The University of Manchester , Manchester M13 9PL, United Kingdom
| | - J N L Connor
- School of Chemistry, The University of Manchester , Manchester M13 9PL, United Kingdom
| | - Gunnar Nyman
- Department of Chemistry and Molecular Biology, University of Gothenburg , 41296 Gothenburg, Sweden
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12
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Espinosa-Garcia J, Rangel C, Corchado JC. Rate constant calculations of the GeH4 + OH/OD → GeH3 + H2O/HOD reactions using an ab initio based full-dimensional potential energy surface. Phys Chem Chem Phys 2016; 18:16941-9. [DOI: 10.1039/c6cp02986h] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
2D representation of the analytical potential energy surface. The saddle point and the complexes in the entry and exit channels are included.
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Affiliation(s)
- J. Espinosa-Garcia
- Departamento de Quimica Fisica and Instituto de Computación Científica Avanzada
- Universidad de Extremadura
- 06071 Badajoz
- Spain
| | - C. Rangel
- Departamento de Quimica Fisica and Instituto de Computación Científica Avanzada
- Universidad de Extremadura
- 06071 Badajoz
- Spain
| | - J. C. Corchado
- Departamento de Quimica Fisica and Instituto de Computación Científica Avanzada
- Universidad de Extremadura
- 06071 Badajoz
- Spain
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13
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Karandashev K, Vaníček J. Accelerating quantum instanton calculations of the kinetic isotope effects. J Chem Phys 2015; 143:194104. [DOI: 10.1063/1.4935701] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- Konstantin Karandashev
- Laboratory of Theoretical Physical Chemistry, Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne CH-1015, Switzerland
| | - Jiří Vaníček
- Laboratory of Theoretical Physical Chemistry, Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne CH-1015, Switzerland
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14
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Liu N, Yang M. An eight-dimensional quantum dynamics study of the Cl + CH4→ HCl + CH3 reaction. J Chem Phys 2015; 143:134305. [DOI: 10.1063/1.4931833] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Na Liu
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Centre for Magnetic Resonance, 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 Centre for Magnetic Resonance, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China
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15
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Hornung B, Harvey JN, Preston TJ, Dunning GT, Orr-Ewing AJ. Empirical Valence Bond Theory Studies of the CH4 + Cl → CH3 + HCl Reaction. J Phys Chem A 2015; 119:9590-8. [DOI: 10.1021/acs.jpca.5b06418] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Balázs Hornung
- School
of Chemistry, University of Bristol, Cantock’s Close, Bristol, BS8 1TS, United Kingdom
| | - Jeremy N. Harvey
- Department
of Chemistry, KU Leuven, Celestijnenlaan 200F, B-3001, Leuven (Heverlee), Belgium
| | - Thomas J. Preston
- School
of Chemistry, University of Bristol, Cantock’s Close, Bristol, BS8 1TS, United Kingdom
| | - Greg T. Dunning
- School
of Chemistry, University of Bristol, Cantock’s Close, Bristol, BS8 1TS, United Kingdom
| | - Andrew J. Orr-Ewing
- School
of Chemistry, University of Bristol, Cantock’s Close, Bristol, BS8 1TS, United Kingdom
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16
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Greene SM, Shan X, Clary DC. Reduced-Dimensionality Semiclassical Transition State Theory: Application to Hydrogen Atom Abstraction and Exchange Reactions of Hydrocarbons. J Phys Chem A 2015; 119:12015-27. [DOI: 10.1021/acs.jpca.5b04379] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Samuel M. Greene
- Physical and Theoretical Chemistry
Laboratory, Department of Chemistry, University of Oxford, South Parks
Road, Oxford, OX1 3QZ, United Kingdom
| | - Xiao Shan
- Physical and Theoretical Chemistry
Laboratory, Department of Chemistry, University of Oxford, South Parks
Road, Oxford, OX1 3QZ, United Kingdom
| | - David C. Clary
- Physical and Theoretical Chemistry
Laboratory, Department of Chemistry, University of Oxford, South Parks
Road, Oxford, OX1 3QZ, United Kingdom
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17
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Oueslati I, Kerkeni B, Tchang-Brillet WÜL, Feautrier N. Quantum scattering study of the abstraction reaction of H atoms from tetramethylsilane. Chem Phys Lett 2015. [DOI: 10.1016/j.cplett.2015.02.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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18
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Shan X, Clary DC. Quantum Dynamics of the Abstraction Reaction of H with Cyclopropane. J Phys Chem A 2014; 118:10134-43. [DOI: 10.1021/jp5087174] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Xiao Shan
- Physical
and Theoretical Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QZ, U.K
| | - David C. Clary
- Physical
and Theoretical Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QZ, U.K
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19
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González-Lavado E, Corchado JC, Espinosa-Garcia J. The hydrogen abstraction reaction O(3P) + CH4: a new analytical potential energy surface based on fit to ab initio calculations. J Chem Phys 2014; 140:064310. [PMID: 24527918 DOI: 10.1063/1.4864358] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Based exclusively on high-level ab initio calculations, a new full-dimensional analytical potential energy surface (PES-2014) for the gas-phase reaction of hydrogen abstraction from methane by an oxygen atom is developed. The ab initio information employed in the fit includes properties (equilibrium geometries, relative energies, and vibrational frequencies) of the reactants, products, saddle point, points on the reaction path, and points on the reaction swath, taking especial caution respecting the location and characterization of the intermediate complexes in the entrance and exit channels. By comparing with the reference results we show that the resulting PES-2014 reproduces reasonably well the whole set of ab initio data used in the fitting, obtained at the CCSD(T) = FULL/aug-cc-pVQZ//CCSD(T) = FC/cc-pVTZ single point level, which represents a severe test of the new surface. As a first application, on this analytical surface we perform an extensive dynamics study using quasi-classical trajectory calculations, comparing the results with recent experimental and theoretical data. The excitation function increases with energy (concave-up) reproducing experimental and theoretical information, although our values are somewhat larger. The OH rotovibrational distribution is cold in agreement with experiment. Finally, our results reproduce experimental backward scattering distribution, associated to a rebound mechanism. These results lend confidence to the accuracy of the new surface, which substantially improves the results obtained with our previous surface (PES-2000) for the same system.
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Affiliation(s)
| | - Jose C Corchado
- Departamento de Química Física, Universidad de Extremadura, 06071 Badajoz, Spain
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Sprung C, Arstad B, Olsbye U. Methane Steam Reforming over a Ni/NiAl2O4Model Catalyst-Kinetics. ChemCatChem 2014. [DOI: 10.1002/cctc.201402017] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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21
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Yan W, Wang D. Quantum reaction dynamics study of vibrational excitation effects on the Cl+CHD3/CD4→HCl/DCl+CD3 reactions. Chem Phys Lett 2014. [DOI: 10.1016/j.cplett.2014.04.026] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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22
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Bender JD, Doraiswamy S, Truhlar DG, Candler GV. Potential energy surface fitting by a statistically localized, permutationally invariant, local interpolating moving least squares method for the many-body potential: Method and application to N4. J Chem Phys 2014; 140:054302. [DOI: 10.1063/1.4862157] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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23
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Shan X, Remmert SM, Clary DC, Zhang B, Liu K. Crossed-beam and reduced dimensionality studies of the state-to-state integral cross sections of the Cl+HCD3(v)→HCl(v′)+CD3 reaction. Chem Phys Lett 2013. [DOI: 10.1016/j.cplett.2013.09.038] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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24
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Monge-Palacios M, Rangel C, Espinosa-Garcia J. Ab initio based potential energy surface and kinetics study of the OH + NH3 hydrogen abstraction reaction. J Chem Phys 2013; 138:084305. [PMID: 23464149 DOI: 10.1063/1.4792719] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
A full-dimensional analytical potential energy surface (PES) for the OH + NH3 → H2O + NH2 gas-phase reaction was developed based exclusively on high-level ab initio calculations. This reaction presents a very complicated shape with wells along the reaction path. Using a wide spectrum of properties of the reactive system (equilibrium geometries, vibrational frequencies, and relative energies of the stationary points, topology of the reaction path, and points on the reaction swath) as reference, the resulting analytical PES reproduces reasonably well the input ab initio information obtained at the coupled-cluster single double triple (CCSD(T)) = FULL/aug-cc-pVTZ//CCSD(T) = FC/cc-pVTZ single point level, which represents a severe test of the new surface. As a first application, on this analytical PES we perform an extensive kinetics study using variational transition-state theory with semiclassical transmission coefficients over a wide temperature range, 200-2000 K. The forward rate constants reproduce the experimental measurements, while the reverse ones are slightly underestimated. However, the detailed analysis of the experimental equilibrium constants (from which the reverse rate constants are obtained) permits us to conclude that the experimental reverse rate constants must be re-evaluated. Another severe test of the new surface is the analysis of the kinetic isotope effects (KIEs), which were not included in the fitting procedure. The KIEs reproduce the values obtained from ab initio calculations in the common temperature range, although unfortunately no experimental information is available for comparison.
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Affiliation(s)
- M Monge-Palacios
- Departamento de Química Física, Universidad de Extremadura, 06071 Badajoz, Spain
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25
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Shan X, Clary DC. Quantum effects in the abstraction reaction by H atoms of primary and secondary hydrogens in n-C4H10: a test of a new potential energy surface construction method. Phys Chem Chem Phys 2013; 15:1222-31. [PMID: 23223355 DOI: 10.1039/c2cp42911j] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Recently, von Horsten et al. suggested an efficient method to construct two dimensional potential energy surfaces (PESs) for use in quantum scattering simulations, in which they utilised the minimum energy path (MEP) and assumed harmonic behaviour of the PES near the MEP. In the same paper, the authors applied this method to various H-abstraction reactions from C1-C3 alkane molecules. In this work we demonstrate an alternative PES construction method, and apply it to the more challenging H-abstraction from n-C(4)H(10) reactions. The geometry optimizations and frequency calculations are done at the MP2/cc-pVTZ level of theory, while the energies are calculated with the CCSD(T) method with the same basis set. The calculations give adiabatic energy barrier heights of 45.9 kJ mol(-1) and 34.4 kJ mol(-1) for the primary and secondary hydrogens in n-C(4)H(10). When compared to purely classical transition state theory, quantum scattering calculations show that quantum tunnelling and zero-point effects have large contributions at low temperatures, typically below 500 K. The branching ratio study suggests that the abstraction of secondary hydrogen in n-C(4)H(10) dominates the overall reaction rate at low temperatures. The rate constants for the two abstraction channels become more comparable as the temperature increases.
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Affiliation(s)
- Xiao Shan
- Physical and Theoretical Chemistry Laboratory, Department of Chemistry, University of Oxford, UK.
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26
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Poutsma ML. Evolution of Structure–Reactivity Correlations for the Hydrogen Abstraction Reaction by Chlorine Atom. J Phys Chem A 2013; 117:687-703. [DOI: 10.1021/jp310970t] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Marvin L. Poutsma
- Chemical Sciences Division, Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, Tennessee
37831-6197, United States
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Shan X, Clary DC. A reduced dimensionality quantum mechanical study of the H + HCF3 ↔ H2 + CF3 reaction. Phys Chem Chem Phys 2013; 15:18530-8. [DOI: 10.1039/c3cp52170b] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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28
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Constructing Potential Energy Surfaces for Polyatomic Systems: Recent Progress and New Problems. ACTA ACUST UNITED AC 2012. [DOI: 10.1155/2012/164752] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Different methods of constructing potential energy surfaces in polyatomic systems are reviewed, with the emphasis put on fitting, interpolation, and analytical (defined by functional forms) approaches, based on quantum chemistry electronic structure calculations. The different approaches are reviewed first, followed by a comparison using the benchmark H + CH4 and the H + NH3 gas-phase hydrogen abstraction reactions. Different kinetics and dynamics properties are analyzed for these reactions and compared with the available experimental data, which permits one to estimate the advantages and disadvantages of each method. Finally, we analyze different problems with increasing difficulty in the potential energy construction: spin-orbit coupling, molecular size, and more complicated reactions with several maxima and minima, which test the soundness and general applicability of each method. We conclude that, although the field of small systems, typically atom-diatom, is mature, there still remains much work to be done in the field of polyatomic systems.
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Zhang B, Liu K, Czakó G, Bowman JM. Translational energy dependence of the Cl + CH4(vb = 0, 1) reactions: a joint crossed-beam and quasiclassical trajectory study. Mol Phys 2012. [DOI: 10.1080/00268976.2012.662600] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Barker JR, Nguyen TL, Stanton JF. Kinetic Isotope Effects for Cl + CH4 ⇌ HCl + CH3 Calculated Using ab Initio Semiclassical Transition State Theory. J Phys Chem A 2012; 116:6408-19. [DOI: 10.1021/jp212383u] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- John R. Barker
- Department of Atmospheric,
Oceanic and Space Sciences, University of Michigan, Ann Arbor, Michigan 48109-2143, United States
| | - Thanh Lam Nguyen
- Department of Atmospheric,
Oceanic and Space Sciences, University of Michigan, Ann Arbor, Michigan 48109-2143, United States
| | - John F. Stanton
- Department of Chemistry
and Biochemistry, The University of Texas, Austin, Texas 78712-0165, United States
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Czakó G, Bowman JM. Accurate ab initio potential energy surface, thermochemistry, and dynamics of the Cl(2P, 2P3/2) + CH4 → HCl + CH3 and H + CH3Cl reactions. J Chem Phys 2012; 136:044307. [DOI: 10.1063/1.3679014] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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32
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Meng F, Yan W, Wang D. Quantum dynamics study of the Cl + CH4 → HCl + CH3 reaction: reactive resonance, vibrational excitation reactivity, and rate constants. Phys Chem Chem Phys 2012; 14:13656-62. [DOI: 10.1039/c2cp41917c] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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33
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Czakó G, Bowman JM. Dynamics of the Reaction of Methane with Chlorine Atom on an Accurate Potential Energy Surface. Science 2011; 334:343-6. [DOI: 10.1126/science.1208514] [Citation(s) in RCA: 154] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Affiliation(s)
- Gábor Czakó
- Cherry L. Emerson Center for Scientific Computation and Department of Chemistry, Emory University, Atlanta, GA 30322, USA
| | - Joel M. Bowman
- Cherry L. Emerson Center for Scientific Computation and Department of Chemistry, Emory University, Atlanta, GA 30322, USA
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34
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von Horsten HF, Banks ST, Clary DC. An efficient route to thermal rate constants in reduced dimensional quantum scattering simulations: Applications to the abstraction of hydrogen from alkanes. J Chem Phys 2011; 135:094311. [DOI: 10.1063/1.3625960] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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35
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Remmert SM, Banks ST, Harvey JN, Orr-Ewing AJ, Clary DC. Reduced dimensionality spin-orbit dynamics of CH3 + HCl ⇌ CH4 + Cl on ab initio surfaces. J Chem Phys 2011; 134:204311. [DOI: 10.1063/1.3592732] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
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36
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Towards automated multi-dimensional quantum dynamical investigations of double-minimum potentials: Principles and example applications. Chem Phys 2011. [DOI: 10.1016/j.chemphys.2010.06.018] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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37
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von Horsten HF, Clary DC. Reactive resonances in the F + CHD3 reaction—a quantum dynamics study. Phys Chem Chem Phys 2011; 13:4340-56. [DOI: 10.1039/c0cp02661a] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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38
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Greaves SJ, Rose RA, Abou-Chahine F, Glowacki DR, Troya D, Orr-Ewing AJ. Quasi-classical trajectory study of the dynamics of the Cl + CH4→ HCl + CH3 reaction. Phys Chem Chem Phys 2011; 13:11438-45. [DOI: 10.1039/c0cp02694h] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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39
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Kawamata H, Liu K. Imaging the nature of the mode-specific chemistry in the reaction of Cl atom with antisymmetric stretch-excited CH4. J Chem Phys 2010; 133:124304. [DOI: 10.1063/1.3482628] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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40
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Xiahou C, Connor JNL. A New Rainbow: Angular Scattering of the F + H2(vi = 0, ji = 0) → FH(vf = 3, jf = 3) + H Reaction. J Phys Chem A 2009; 113:15298-306. [DOI: 10.1021/jp906042g] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Chengkui Xiahou
- School of Chemistry, The University of Manchester, Manchester M13 9PL, England
| | - J. N. L. Connor
- School of Chemistry, The University of Manchester, Manchester M13 9PL, England
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42
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Banks ST, Tautermann CS, Remmert SM, Clary DC. An improved treatment of spectator mode vibrations in reduced dimensional quantum dynamics: Application to the hydrogen abstraction reactions μ+CH4, H+CH4, D+CH4, and CH3+CH4. J Chem Phys 2009; 131:044111. [DOI: 10.1063/1.3177380] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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43
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Taylor MS, Ivanic SA, Wood GPF, Easton CJ, Bacskay GB, Radom L. Hydrogen Abstraction by Chlorine Atom from Small Organic Molecules Containing Amino Acid Functionalities: An Assessment of Theoretical Procedures. J Phys Chem A 2009; 113:11817-32. [DOI: 10.1021/jp9029437] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- Mark S. Taylor
- ARC Centre of Excellence for Free Radical Chemistry and Biotechnology, School of Chemistry, University of Sydney, Sydney, NSW 2006, Australia, and Research School of Chemistry, Australian National University, Canberra, ACT 0200, Australia
| | - Sandra A. Ivanic
- ARC Centre of Excellence for Free Radical Chemistry and Biotechnology, School of Chemistry, University of Sydney, Sydney, NSW 2006, Australia, and Research School of Chemistry, Australian National University, Canberra, ACT 0200, Australia
| | - Geoffrey P. F. Wood
- ARC Centre of Excellence for Free Radical Chemistry and Biotechnology, School of Chemistry, University of Sydney, Sydney, NSW 2006, Australia, and Research School of Chemistry, Australian National University, Canberra, ACT 0200, Australia
| | - Christopher J. Easton
- ARC Centre of Excellence for Free Radical Chemistry and Biotechnology, School of Chemistry, University of Sydney, Sydney, NSW 2006, Australia, and Research School of Chemistry, Australian National University, Canberra, ACT 0200, Australia
| | - George B. Bacskay
- ARC Centre of Excellence for Free Radical Chemistry and Biotechnology, School of Chemistry, University of Sydney, Sydney, NSW 2006, Australia, and Research School of Chemistry, Australian National University, Canberra, ACT 0200, Australia
| | - Leo Radom
- ARC Centre of Excellence for Free Radical Chemistry and Biotechnology, School of Chemistry, University of Sydney, Sydney, NSW 2006, Australia, and Research School of Chemistry, Australian National University, Canberra, ACT 0200, Australia
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Corchado JC, Bravo JL, Espinosa-Garcia J. The hydrogen abstraction reaction H + CH4. I. New analytical potential energy surface based on fitting to ab initio calculations. J Chem Phys 2009; 130:184314. [PMID: 19449928 DOI: 10.1063/1.3132223] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
A new analytical potential energy surface is presented for the reaction of hydrogen abstraction from methane by a hydrogen atom. It is based on an analytical expression proposed by Jordan and Gilbert [J. Chem. Phys. 102, 5669 (1995)], and its fittable parameters were obtained by a multibeginning optimization procedure to reproduce high-level ab initio electronic structure calculations obtained at the CCSD(T)/cc-pVTZ level. The ab initio information employed in the fit includes properties (equilibrium geometries, relative energies, and vibrational frequencies) of the reactants, products, saddle point, points on the reaction path, and points on the reaction swath. No experimental information is used. By comparison with the reference results we show that the resulting surface reproduces well not only the ab initio data used in the fitting but also other thermochemical and kinetic results computed at the same ab initio level, such as equilibrium constants, rate constants, and kinetic isotope effects, which were not used in the fit. In this way we show that the new potential energy surface is correctly fitted and almost as accurate as the CCSD(T)/cc-pVTZ method in describing the kinetics of the reaction. We analyze the limitations of the functional form and the fitting method employed, and suggest some solutions to their drawbacks. In a forthcoming communication, we test the quality of the new surface by comparing its results with experimental values.
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Affiliation(s)
- Jose C Corchado
- Departamento de Química Física, Universidad de Extremadura, 06071 Badajoz, Spain.
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45
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Remmert SM, Banks ST, Clary DC. Reduced Dimensionality Quantum Dynamics of CH3 + CH4 → CH4 + CH3: Symmetric Hydrogen Exchange on an Ab Initio Potential. J Phys Chem A 2009; 113:4255-64. [DOI: 10.1021/jp810803k] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Sarah M. Remmert
- Department of Chemistry, University of Oxford, PTCL, South Parks Road, Oxford, OX13QZ, United Kingdom
| | - Simon T. Banks
- Department of Chemistry, University of Oxford, PTCL, South Parks Road, Oxford, OX13QZ, United Kingdom
| | - David C. Clary
- Department of Chemistry, University of Oxford, PTCL, South Parks Road, Oxford, OX13QZ, United Kingdom
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46
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Banks ST, Clary DC. Chemical reaction surface vibrational frequencies evaluated in curvilinear internal coordinates: Application to H+CH4⇌H2+CH3. J Chem Phys 2009; 130:024106. [DOI: 10.1063/1.3052076] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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47
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Crim FF. Chemical dynamics of vibrationally excited molecules: Controlling reactions in gases and on surfaces. Proc Natl Acad Sci U S A 2008; 105:12654-61. [PMID: 18765816 PMCID: PMC2529117 DOI: 10.1073/pnas.0803010105] [Citation(s) in RCA: 134] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2008] [Indexed: 11/18/2022] Open
Abstract
Experimental studies of the chemical reaction dynamics of vibrationally excited molecules reveal the ability of different vibrations to control the course of a reaction. This Perspective describes those studies for the prototypical reaction of vibrationally excited methane and its isotopologues in gases and on surfaces and looks to the prospects of similar studies in liquids. The influences of vibrational excitation on the C-H bond cleavage in a single collision reaction with Cl and in dissociative adsorption on a Ni surface bear some striking similarities. Both reactions are bond-selective processes in which the initial preparation of a molecular eigenstate containing a large component of C-H stretching results in preferential cleavage of that bond. It is possible to cleave either the C-H bond or C-D bond in the reaction of Cl with CH3D, CH2D2, or CHD3 and, similarly, to use initial excitation of the C-H stretch to promote dissociation of CHD3 to CD3 and H on a Ni surface. Different vibrational modes, such as the symmetric and antisymmetric stretches in CH3D or CH4, lead to very different reactivities, and molecules with the symmetric stretching vibration excited can be as much as 10 times more reactive than ones with the antisymmetric stretch excited. The origin of this behavior lies in the change in the vibrational motion induced by the interaction with the atomic reaction partner or the surface.
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Affiliation(s)
- F Fleming Crim
- Department of Chemistry, University of Wisconsin, Madison, WI 53706, USA.
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48
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Arnaut L, Formosinho S. Understanding Chemical Reactivity: The Case for Atom, Proton and Methyl Transfers. Chemistry 2008; 14:6578-87. [DOI: 10.1002/chem.200701986] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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49
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Eskola AJ, Timonen RS, Marshall P, Chesnokov EN, Krasnoperov LN. Rate Constants and Hydrogen Isotope Substitution Effects in the CH3 + HCl and CH3 + Cl2 Reactions. J Phys Chem A 2008; 112:7391-401. [DOI: 10.1021/jp801999w] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Arkke J. Eskola
- Laboratory of Physical Chemistry, P.O. Box 55, FIN-00014 University of Helsinki, Finland, Department of Chemistry, University of North Texas, P.O., Box 305070, Denton, Texas 76203-5070, Institute of Chemical Kinetics and Combustion, Institutskaya 3, Novosibirsk, 630090, Russia, and Department of Chemistry and Environmental Science, New Jersey Institute of Technology, Newark, New Jersey 07102
| | - Raimo S. Timonen
- Laboratory of Physical Chemistry, P.O. Box 55, FIN-00014 University of Helsinki, Finland, Department of Chemistry, University of North Texas, P.O., Box 305070, Denton, Texas 76203-5070, Institute of Chemical Kinetics and Combustion, Institutskaya 3, Novosibirsk, 630090, Russia, and Department of Chemistry and Environmental Science, New Jersey Institute of Technology, Newark, New Jersey 07102
| | - Paul Marshall
- Laboratory of Physical Chemistry, P.O. Box 55, FIN-00014 University of Helsinki, Finland, Department of Chemistry, University of North Texas, P.O., Box 305070, Denton, Texas 76203-5070, Institute of Chemical Kinetics and Combustion, Institutskaya 3, Novosibirsk, 630090, Russia, and Department of Chemistry and Environmental Science, New Jersey Institute of Technology, Newark, New Jersey 07102
| | - Evgeni N. Chesnokov
- Laboratory of Physical Chemistry, P.O. Box 55, FIN-00014 University of Helsinki, Finland, Department of Chemistry, University of North Texas, P.O., Box 305070, Denton, Texas 76203-5070, Institute of Chemical Kinetics and Combustion, Institutskaya 3, Novosibirsk, 630090, Russia, and Department of Chemistry and Environmental Science, New Jersey Institute of Technology, Newark, New Jersey 07102
| | - Lev N. Krasnoperov
- Laboratory of Physical Chemistry, P.O. Box 55, FIN-00014 University of Helsinki, Finland, Department of Chemistry, University of North Texas, P.O., Box 305070, Denton, Texas 76203-5070, Institute of Chemical Kinetics and Combustion, Institutskaya 3, Novosibirsk, 630090, Russia, and Department of Chemistry and Environmental Science, New Jersey Institute of Technology, Newark, New Jersey 07102
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50
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Ab initio study of the CD4+Cl⇄CD3+DCl equilibrium. Thermochemistry of the CD3 radical. Chem Phys 2007. [DOI: 10.1016/j.chemphys.2007.09.060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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