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Roaming dynamics of the H+C 2D 2 reaction on a fundamental-invariant neural network potential energy surface. CHINESE J CHEM PHYS 2022. [DOI: 10.1063/1674-0068/cjcp2111249] [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]
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Fu YL, Bai Y, Han YC, Fu B, Zhang DH. Double-Roaming Dynamics in the H + C 2H 2 → H 2 + C 2H Reaction: Acetylene-Facilitated Roaming and Vinylidene-Facilitated Roaming. J Phys Chem Lett 2021; 12:4211-4217. [PMID: 33900762 DOI: 10.1021/acs.jpclett.1c01045] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
We report two novel roaming pathways for the H + C2H2 → H2 + C2H reaction by performing extensive quasiclassical trajectory calculations on a new, global, high-level machine learning-based potential energy surface. One corresponds to the acetylene-facilitated roaming pathway, where the H atom turns back from the acetylene + H channel and abstracts another H atom from acetylene. The other is the vinylidene-facilitated roaming, where the H atom turns back from the vinylidene + H channel and abstracts another H from vinylidene. The "double-roaming" pathways account for roughly 95% of the total cross section of the H2 + C2H products at the collision energy of 70 kcal/mol. These computational results give valuable insights into the significance of the two isomers (acetylene and vinylidene) in chemical reaction dynamics and also the experimental search for roaming dynamics in this bimolecular reaction.
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Affiliation(s)
- Yan-Lin Fu
- School of Physics, Dalian University of Technology, Dalian, China116024
- State Key Laboratory of Molecular Reaction Dynamics and Center for Theoretical and Computational Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, China 116023
| | - Yuyao Bai
- School of Physics, Dalian University of Technology, Dalian, China116024
- State Key Laboratory of Molecular Reaction Dynamics and Center for Theoretical and Computational Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, China 116023
| | - Yong-Chang Han
- School of Physics, Dalian University of Technology, Dalian, China116024
| | - Bina Fu
- State Key Laboratory of Molecular Reaction Dynamics and Center for Theoretical and Computational Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, China 116023
| | - Dong H Zhang
- State Key Laboratory of Molecular Reaction Dynamics and Center for Theoretical and Computational Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, China 116023
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Bowman MC, Burke AD, Turney JM, Schaefer III HF. Conclusive determination of ethynyl radical hydrogen abstraction energetics and kinetics*. Mol Phys 2020. [DOI: 10.1080/00268976.2020.1769214] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Affiliation(s)
- Michael C. Bowman
- Center for Computational Quantum Chemistry, University of Georgia, Athens, GA, USA
- Department of Chemistry and Biochemistry, Taylor University, Upland, IN, USA
| | - Alexandra D. Burke
- Center for Computational Quantum Chemistry, University of Georgia, Athens, GA, USA
| | - Justin M. Turney
- Center for Computational Quantum Chemistry, University of Georgia, Athens, GA, USA
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Bowman MC, Burke AD, Turney JM, Schaefer HF. Mechanisms of the Ethynyl Radical Reaction with Molecular Oxygen. J Phys Chem A 2018; 122:9498-9511. [PMID: 30421915 DOI: 10.1021/acs.jpca.8b09862] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The ethynyl radical, •C2H, is a key intermediate in the combustion of various alkynes. Once produced, the ethynyl radical will rapidly react with molecular oxygen to produce a variety of products. This research presents the first comprehensive high level theoretical study of the reaction of the •C2H (2Σ+) radical with molecular oxygen (3Σg-). Correlation methods as complete as CCSDT(Q) were used; basis sets as large as cc-pV6Z were adopted. Focal point analysis was employed to approach relative energies within the bounds of chemical accuracy (≤1 kcal mol-1). Two dominate reaction pathways from the ethynyl peroxy radical include oxygen-oxygen cleavage from the ethynyl peroxy radical that is initially formed to produce HCCO (2A″) and O (3P) and an isomerization of the ethynyl peroxy radical to eventually yield HCO (2A') and CO (1Σ+). The branching ratio between these two competitive reaction pathways was determined to be 1:1 at 298 K. Minor reaction pathways leading to the production of CO2 (1Σg+) and CH (2Π, 4Σ-, 2Δ) were also characterized. The absence of CCO (3Σ-) and OH (2Π) was explained in terms competition with more accessible reaction pathways.
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Affiliation(s)
- Michael C Bowman
- Center for Computational Quantum Chemistry , University of Georgia , Athens , Georgia 30602 United States
| | - Alexandra D Burke
- Center for Computational Quantum Chemistry , University of Georgia , Athens , Georgia 30602 United States
| | - Justin M Turney
- Center for Computational Quantum Chemistry , University of Georgia , Athens , Georgia 30602 United States
| | - Henry F Schaefer
- Center for Computational Quantum Chemistry , University of Georgia , Athens , Georgia 30602 United States
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Dagdigian PJ. Interaction of C 2H with molecular hydrogen: Ab initio potential energy surface and scattering calculations. J Chem Phys 2018; 148:024304. [PMID: 29331109 DOI: 10.1063/1.5006149] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The potential energy surface (PES) describing the interaction of the ethynyl (C2H) radical in its ground X̃2Σ+ electronic state with molecular hydrogen has been computed through restricted coupled cluster calculations including single, double, and (perturbative) triple excitations [RCCSD(T)], with the assumption of fixed molecular geometries. The computed points were fit to an analytical form suitable for time-independent quantum scattering calculations of rotationally inelastic cross sections and rate constants. A representative set of energy dependent state-to-state cross sections is presented and discussed. The PES and cross sections for collisions of H2(j = 0) are compared with a previous study [F. Najar et al., Chem. Phys. Lett. 614, 251 (2014)] of collisions of C2H with H2 treated as a spherical collision partner. Good agreement is found between the two sets of calculations when the H2 molecule in the present calculation is spherically averaged.
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Affiliation(s)
- Paul J Dagdigian
- Department of Chemistry, The Johns Hopkins University, Baltimore, Maryland 21218-2685, USA
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Chen L, Shao K, Chen J, Yang M, Zhang DH. Full-dimensional quantum dynamics study of the H2 + C2H → H + C2H2 reaction on an ab initio potential energy surface. J Chem Phys 2016; 144:194309. [DOI: 10.1063/1.4948996] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Liuyang Chen
- Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National for Magnetic Resonance in Wuhan, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China
- University of Chinese Academy of Sciences, Beijing 100049, People’s Republic of China
| | - Kejie Shao
- University of Chinese Academy of Sciences, Beijing 100049, People’s Republic of China
- State Key Laboratory of Molecular Reaction Dynamics and Center for Theoretical Computational Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, People’s Republic of China
| | - Jun Chen
- University of Chinese Academy of Sciences, Beijing 100049, People’s Republic of China
- State Key Laboratory of Molecular Reaction Dynamics and Center for Theoretical Computational Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, 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, National for Magnetic Resonance in Wuhan, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China
| | - Dong H. Zhang
- State Key Laboratory of Molecular Reaction Dynamics and Center for Theoretical Computational Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, People’s Republic of China
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Collisional excitation of C 2 H(X 2 Σ + ) by para-H 2 ( j = 0): Fine-structure resolved transitions. Chem Phys Lett 2014. [DOI: 10.1016/j.cplett.2014.09.014] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Matsugi A, Takayanagi T. Mode selective dynamics and kinetics of the H2 + F2 → H + HF + F reaction. Phys Chem Chem Phys 2014; 16:22517-26. [DOI: 10.1039/c4cp03362k] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The reactivity is significantly enhanced by vibrational excitation of F2 whereas excitation of H2 vibration has a moderate effect.
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Affiliation(s)
- Akira Matsugi
- National Institute of Advanced Industrial Science and Technology (AIST)
- Tsukuba, Japan
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