1
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Gál DR, Papp D, Czakó G. Benchmark ab initio characterization of the multi-channel Cl + CH 3X [X = F, Cl, Br, I] reactive potential energy surfaces. Phys Chem Chem Phys 2024; 26:17695-17706. [PMID: 38869051 DOI: 10.1039/d4cp01578a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2024]
Abstract
We determine benchmark geometries and relative energies for the stationary points of the Cl + CH3X [X = F, Cl, Br, I] reactions. We consider four possible reaction pathways: hydrogen abstraction, hydrogen substitution, halogen abstraction, and halogen substitution, where the substitution processes can proceed via either Walden inversion or front-side attack. We perform geometry optimizations and obtain harmonic vibrational frequencies at the explicitly-correlated UCCSD(T)-F12b/aug-cc-pVTZ level of theory, followed by UCCSD(T)-F12b/aug-cc-pVQZ single-point computations to make finite-basis-set error negligible. To reach chemical (<1 kcal mol-1), or even subchemical (<0.5 kcal mol-1) accuracy, we include core-correlation, scalar relativistic, post-(T), spin-orbit-splitting and zero-point-energy contributions, as well, in the relative energies of all the stationary points. Our benchmark 0 K reaction enthalpies are compared to available experimental results and show good agreement. The stationary-point structures and energetics are interpreted in terms of Hammond's postulate and used to make predictions related to the dynamical behavior of these reactive systems.
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Affiliation(s)
- Dorina R Gál
- 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.
| | - 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, 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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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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3
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Robertson C, Paterson MJ. Velocity map images from surface-hopping; reactive scattering of OH ( 2Σ +) + H 2 ( 1Σ+g). Chem Commun (Camb) 2022; 58:9092-9095. [PMID: 35894124 DOI: 10.1039/d2cc03368b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We study OH(Σ) + H2 → H2O(X) + H reactive scattering using two potential energy models found in the literature. We analyze the quenching channels and generate velocity map images (VMI) by simulating quantum-classical trajectories of the quenched products. The initial conditions attempt to simulate supersonic jet, molecular beam scattering experiments which we compare against. The simulated results are able to elucidate the mechanisms behind some of these experimental observations.
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Affiliation(s)
- Christopher Robertson
- School of Engineering & Physical Sciences, Heriot-Watt University, Edinburgh, Scotland EH14 4AS, UK.
| | - Martin J Paterson
- School of Engineering & Physical Sciences, Heriot-Watt University, Edinburgh, Scotland EH14 4AS, UK.
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4
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Tóth P, Szűcs T, Czakó G. Benchmark Ab Initio Characterization of the Abstraction and Substitution Pathways of the Cl + CH 3CN Reaction. J Phys Chem A 2022; 126:2802-2810. [PMID: 35482972 PMCID: PMC9109142 DOI: 10.1021/acs.jpca.2c01376] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
![]()
We investigate the
reaction pathways of the Cl + CH3CN system: hydrogen abstraction,
methyl substitution, hydrogen substitution,
and cyanide substitution, leading to HCl + CH2CN, ClCN/CNCl
+ CH3, ClCH2CN + H, and CH3Cl + CN,
respectively. Hydrogen abstraction is exothermic and has a low barrier,
whereas the other channels are endothermic with high barriers. The
latter two can proceed via a Walden inversion or front-side attack
mechanism, and the front-side attack barriers are always higher. The
C-side methyl substitution has a lower barrier and also a lower endothermicity
than the N-side reaction. The computations utilize an accurate composite
ab initio approach and the explicitly correlated CCSD(T)-F12b method.
The benchmark classical and vibrationally adiabatic energies of the
stationary points are determined with the most accurate CCSD(T)-F12b/aug-cc-pVQZ
energies adding further contributions of the post-(T) and core correlation,
scalar relativistic effects, spin–orbit coupling, and zero-point
energy corrections. These contributions are found to be non-negligible
to reach subchemical accuracy.
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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
| | - 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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5
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Qin J, Li J, Li J. Quasi-classical trajectory investigation of H + SO2 → OH + SO reaction on full-dimensional accurate potential energy surface. CHINESE J CHEM PHYS 2021. [DOI: 10.1063/1674-0068/cjcp2107112] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Affiliation(s)
- Jie Qin
- School of Chemistry and Chemical Engineering & Chongqing Key Laboratory of Theoretical and Computational Chemistry, Chongqing University, Chongqing 401331, China
| | - Jia Li
- School of Chemistry and Chemical Engineering & Chongqing Key Laboratory of Theoretical and Computational Chemistry, Chongqing University, Chongqing 401331, China
| | - Jun Li
- School of Chemistry and Chemical Engineering & Chongqing Key Laboratory of Theoretical and Computational Chemistry, Chongqing University, Chongqing 401331, China
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6
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Papp D, Tajti V, Győri T, Czakó G. Theory Finally Agrees with Experiment for the Dynamics of the Cl + C 2H 6 Reaction. J Phys Chem Lett 2020; 11:4762-4767. [PMID: 32441943 PMCID: PMC7309313 DOI: 10.1021/acs.jpclett.0c01263] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2020] [Accepted: 05/22/2020] [Indexed: 05/07/2023]
Abstract
Since the pioneering reaction dynamics studies of H + H2 in the 1970s, theory increased the system size by one atom in every decade arriving to six-atom reactions in the early 2010s. Here, we take a significant step forward by reporting accurate dynamics simulations for the nine-atom Cl + ethane (C2H6) reaction using a new high-quality spin-orbit-ground-state ab initio potential energy surface. Quasi-classical trajectory simulations on this surface cool the rotational distribution of the HCl product molecules, thereby providing unprecedented agreement with experiment after several previous failed attempts of theory. Unlike Cl + CH4, the Cl + C2H6 reaction is exothermic with an adiabatically submerged transition state, allowing testing of the validity of the Polanyi rules for a negative-barrier reaction.
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Affiliation(s)
- 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, Rerrich Béla tér 1, Szeged H-6720, Hungary
| | - 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, 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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7
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Liu Y, Li J. An accurate potential energy surface and ring polymer molecular dynamics study of the Cl + CH4→ HCl + CH3reaction. Phys Chem Chem Phys 2020; 22:344-353. [DOI: 10.1039/c9cp05693a] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Thermal rate coefficients for the Cl + CH4/CD4reactions were studied on a new full-dimensional accurate potential energy surface with the spin–orbit corrections considered in the entrance channel.
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Affiliation(s)
- Yang Liu
- School of Chemistry and Chemical Engineering
- Chongqing University
- Chongqing 401331
- China
| | - Jun Li
- School of Chemistry and Chemical Engineering
- Chongqing University
- Chongqing 401331
- China
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8
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Troya D. Ab Initio and Quasiclassical Trajectory Study of the O( 3P) + 2-Propanol Hydrogen Abstraction Reaction. J Phys Chem A 2019; 123:6911-6920. [PMID: 31322893 DOI: 10.1021/acs.jpca.9b06065] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
We present a theoretical study of the hydrogen abstraction reaction from 2-propanol by ground-state oxygen atoms. First, ab initio calculations are used to characterize the stationary points of the potential energy surface. Rotation around the C-C-O-H dihedral affords two conformers in 2-propanol, which gives rise to 13 hydrogen abstraction reaction pathways grouped into three channels, Cα, Cβ, and O, depending on the abstraction site. Reaction at Cα exhibits the lowest barrier and largest exothermicity, followed by reaction at Cβ, and at 2-propanol's oxygen atom. Additional ab initio calculations beyond the stationary points are employed to obtain a grid of energies with which a specific-reaction-parameters (SRP) PM6 semiemipirical Hamiltonian is derived for the title reaction. The SRP-PM6 model captures the energetics of the reaction with higher accuracy than some conventional first-principles methods but is efficient enough to allow for extensive reaction dynamics calculations. Quasiclassical trajectories are subsequently propagated with the SRP-PM6 Hamiltonian to obtain reaction dynamics properties that are compared to experiments. Product translational energy and angular distributions for reaction at Cα with the two conformers of 2-propanol are in good agreement with recent molecular-beam measurements, and they exhibit largely backward scattering with modest energy release to relative translation. Most of the energy is deposited into the organic product, substantiating a reaction mechanism dominated by rebound dynamics.
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Affiliation(s)
- Diego Troya
- Department of Chemistry , Virginia Tech , 1040 Drillfield Dr. , Blacksburg , Virginia 24061 , United States
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9
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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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10
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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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11
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Vereecken L, Glowacki DR, Pilling MJ. Theoretical Chemical Kinetics in Tropospheric Chemistry: Methodologies and Applications. Chem Rev 2015; 115:4063-114. [DOI: 10.1021/cr500488p] [Citation(s) in RCA: 146] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Luc Vereecken
- Max Planck Institute for Chemistry, 55128 Mainz, Germany
| | - David R. Glowacki
- PULSE
Institute and Department of Chemistry, Stanford University, Stanford, California 94305, United States
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
- School
of Chemistry, University of Bristol, Bristol BS8 1TS, United Kingdom
- Department
of Computer Science, University of Bristol, Bristol BS8 1UB, United Kingdom
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12
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Preston TJ, Dunning GT, Orr-Ewing AJ, Vázquez SA. Direct and Indirect Hydrogen Abstraction in Cl + Alkene Reactions. J Phys Chem A 2014; 118:5595-607. [DOI: 10.1021/jp5042734] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- 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
| | - Saulo A. Vázquez
- Departamento de Química
Física and Centro Singular de Investigación Química
Biológica y Materiales Moleculares, Campus Vida, Universidad de Santiago de Compostela, 15782 Santiago
de Compostela, Spain
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13
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Jiang B, Guo H. Mode Specificity, Bond Selectivity, and Product Energy Disposal in X + CH4/CHD3(X=H, F, O(3P), Cl, and OH) Hydrogen Abstraction Reactions: Perspective from Sudden Vector Projection Model. J CHIN CHEM SOC-TAIP 2014. [DOI: 10.1002/jccs.201400158] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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14
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Czakó G, Bowman JM. Reaction Dynamics of Methane with F, O, Cl, and Br on ab Initio Potential Energy Surfaces. J Phys Chem A 2014; 118:2839-64. [DOI: 10.1021/jp500085h] [Citation(s) in RCA: 89] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Gábor Czakó
- Laboratory of Molecular Structure and Dynamics,
Institute of Chemistry, Eötvös University, H-1518 Budapest 112, P.O. Box 32, Hungary
| | - Joel M. Bowman
- Cherry
L. Emerson Center for Scientific Computation and Department of Chemistry, Emory University, Atlanta, Georgia 30322, United States
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15
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Czakó G, Liu R, Yang M, Bowman JM, Guo H. Quasiclassical Trajectory Studies of the O(3P) + CX4(vk = 0, 1) → OX(v) + CX3(n1n2n3n4) [X = H and D] Reactions on an Ab Initio Potential Energy Surface. J Phys Chem A 2013; 117:6409-20. [DOI: 10.1021/jp4038107] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Gábor Czakó
- Laboratory of Molecular Structure
and Dynamics, Institute of Chemistry, Eötvös University, H-1518, Budapest 112, P.O. Box 32, Hungary
| | - Rui Liu
- Key Laboratory of Magnetic Resonance
in Biological Systems, 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, People’s Republic
of China
| | - Minghui Yang
- Key Laboratory of Magnetic Resonance
in Biological Systems, 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, People’s Republic
of China
| | - Joel M. Bowman
- Cherry L. Emerson
Center for Scientific
Computation and Department of Chemistry, Emory University, Atlanta, Georgia 30322, United States
| | - Hua Guo
- Department of Chemistry and
Chemical Biology, University of New Mexico, Albuquerque, New Mexico 87131, United States
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16
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Berke AE, Volpa EH, Annesley CJ, Crim FF. The influence of translational and vibrational energy on the reaction of Cl with CH3D. J Chem Phys 2013; 138:224306. [DOI: 10.1063/1.4808378] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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17
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CHENG DAHAI, YANG TIANGANG, CHEN MAODU. STEREODYNAMICS STUDY OF THE ABSTRACTION REACTION H + CD4 → HD + CD3. JOURNAL OF THEORETICAL & COMPUTATIONAL CHEMISTRY 2013. [DOI: 10.1142/s021963361250109x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
A new London–Eyring–Polanyi–Sato (LEPS) potential energy surface (PES) is employed in this work to study the stereo properties for the abstraction reaction of hydrogen with methane at its rovibrationally ground state using the quasiclassical trajectory method (QCT). A "quasi-triatomic" approximation is used to treat the CD3 group of CD4 as a pseudoatom. The calculated excitation function of the title reaction can give a good agreement to most experimental and theoretical data at collision energies (Ec =1.5 ~ 2.5 eV ). Further investigation of the product HD in reaction H + CD4 (v = 0, j = 0) → HD + CD3 and D + CH4 (v = 0, j = 0) → HD + CH3 shows the dependence of the product rotational polarization on collision energies and mass factor, but P(θr) is not sensitive to both the collision energies and the mass factor.
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Affiliation(s)
- DAHAI CHENG
- School of Physics and Optoelectronic Technology, and College of Advanced Science and Technology, Dalian University of Technology, Dalian 116024, P. R. China
| | - TIANGANG YANG
- School of Physics and Optoelectronic Technology, and College of Advanced Science and Technology, Dalian University of Technology, Dalian 116024, P. R. China
| | - MAODU CHEN
- School of Physics and Optoelectronic Technology, and College of Advanced Science and Technology, Dalian University of Technology, Dalian 116024, P. R. China
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18
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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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19
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Czakó G. Gaussian binning of the vibrational distributions for the Cl + CH4(v(4/2) = 0, 1) → H + CH3Cl(n(1)n(2)n(3)n(4)n(5)n(6)) reactions. J Phys Chem A 2012; 116:7467-73. [PMID: 22721354 DOI: 10.1021/jp3044797] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We test several binning techniques to obtain mode-specific final-state distributions for polyatomic reactions. Normal mode analysis is done after an exact transformation to the Eckart frame. Standard histogram binning (HB) and three different variants of the energy-based Gaussian binning (1GB) are employed to obtain the probabilities of the vibrational states. We consider the two major issues of the polyatomic quasiclassical product analysis, i.e., (1) rounding the classical action to the nearest integer can result in unphysical states and (2) the normal-mode analysis can break down for highly distorted geometries. We show that 1GB can handle issue 1 when the total vibrational energy is evaluated in the normal mode space using the harmonic approximation and both issues 1 and 2 can be solved when the total vibrational energy is calculated exactly in the Cartesian space. We found that anharmonicity in the quantized energy levels does not have a significant effect on the final-state distributions. Quasiclassical trajectory calculations are performed for the reactant ground-state and bending-excited Cl((2)P(3/2)) + CH(4)(v(4/2) = 0, 1) → H + CH(3)Cl reactions using an ab initio potential energy surface. The product analysis techniques are successfully applied to the CH(3)Cl product molecules and some qualitative features of the results are discussed.
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Affiliation(s)
- Gábor Czakó
- Laboratory of Molecular Structure and Dynamics, Institute of Chemistry, Eötvös University, H-1518 Budapest 112, P.O. Box 32,Hungary.
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20
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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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21
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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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