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Direct ab initio dynamics study of rate constants and kinetic isotope effects for C-2(A(3)Pi(u)) + CH3OH reaction

Huo, Rui-Ping; Zhang, Xiang; Huang, Xu-Ri; Li, Jilai LU and Sun, Chia-Chung (2012) In Molecular Physics 110(18). p.2205-2217
Abstract
The hydrogen abstraction of CH3OH by C-2 (A(3)Pi(u)) has been investigated by direct ab initio dynamics over a wide temperature range 200-3000 K. The potential energy surfaces (PESs) have been constructed at the UCCSD(T)/aug-cc-pVTZ//UMP2/6-311++G(d,p) levels of theory. Two different hydrogen abstractions on the methyl and hydroxyl sites of methanol are considered. For the methyl H-abstraction, it is essentially a hydrogen atom transfer (HAT), whereas the hydroxyl site H-abstraction is better described as a proton coupled electron transfer (PCET) according to the Natural Bond Orbital (NBO) analysis. The results suggest that the methyl site reaction is dominant, and the calculated rate constants are roughly consistent with available... (More)
The hydrogen abstraction of CH3OH by C-2 (A(3)Pi(u)) has been investigated by direct ab initio dynamics over a wide temperature range 200-3000 K. The potential energy surfaces (PESs) have been constructed at the UCCSD(T)/aug-cc-pVTZ//UMP2/6-311++G(d,p) levels of theory. Two different hydrogen abstractions on the methyl and hydroxyl sites of methanol are considered. For the methyl H-abstraction, it is essentially a hydrogen atom transfer (HAT), whereas the hydroxyl site H-abstraction is better described as a proton coupled electron transfer (PCET) according to the Natural Bond Orbital (NBO) analysis. The results suggest that the methyl site reaction is dominant, and the calculated rate constants are roughly consistent with available experimental values. On the other hand, the temperature dependence of deuterium kinetic isotope effects (KIEs) analysis reveals a substantial normal isotope effect in the methyl H-abstraction process, while normal and inverse KIEs coexist in the hydroxyl H-abstraction channel. Furthermore, the three and four-parameter expressions of Arrhenius rate constants are also provided within 200-3000 K. (Less)
Please use this url to cite or link to this publication:
author
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
C-2, rate constants, temperature dependence, KIE
in
Molecular Physics
volume
110
issue
18
pages
2205 - 2217
publisher
Taylor & Francis
external identifiers
  • wos:000309122700007
  • scopus:84867055083
ISSN
1362-3028
DOI
10.1080/00268976.2012.668969
language
English
LU publication?
yes
id
984914ec-8dde-43f6-b0aa-47ca0c908486 (old id 3191648)
date added to LUP
2012-11-27 07:53:50
date last changed
2017-01-01 03:18:21
@article{984914ec-8dde-43f6-b0aa-47ca0c908486,
  abstract     = {The hydrogen abstraction of CH3OH by C-2 (A(3)Pi(u)) has been investigated by direct ab initio dynamics over a wide temperature range 200-3000 K. The potential energy surfaces (PESs) have been constructed at the UCCSD(T)/aug-cc-pVTZ//UMP2/6-311++G(d,p) levels of theory. Two different hydrogen abstractions on the methyl and hydroxyl sites of methanol are considered. For the methyl H-abstraction, it is essentially a hydrogen atom transfer (HAT), whereas the hydroxyl site H-abstraction is better described as a proton coupled electron transfer (PCET) according to the Natural Bond Orbital (NBO) analysis. The results suggest that the methyl site reaction is dominant, and the calculated rate constants are roughly consistent with available experimental values. On the other hand, the temperature dependence of deuterium kinetic isotope effects (KIEs) analysis reveals a substantial normal isotope effect in the methyl H-abstraction process, while normal and inverse KIEs coexist in the hydroxyl H-abstraction channel. Furthermore, the three and four-parameter expressions of Arrhenius rate constants are also provided within 200-3000 K.},
  author       = {Huo, Rui-Ping and Zhang, Xiang and Huang, Xu-Ri and Li, Jilai and Sun, Chia-Chung},
  issn         = {1362-3028},
  keyword      = {C-2,rate constants,temperature dependence,KIE},
  language     = {eng},
  number       = {18},
  pages        = {2205--2217},
  publisher    = {Taylor & Francis},
  series       = {Molecular Physics},
  title        = {Direct ab initio dynamics study of rate constants and kinetic isotope effects for C-2(A(3)Pi(u)) + CH3OH reaction},
  url          = {http://dx.doi.org/10.1080/00268976.2012.668969},
  volume       = {110},
  year         = {2012},
}