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Title: Communication: Rigorous quantum dynamics of O + O{sub 2} exchange reactions on an ab initio potential energy surface substantiate the negative temperature dependence of rate coefficients

Abstract

The kinetics and dynamics of several O + O{sub 2} isotope exchange reactions have been investigated on a recently determined accurate global O{sub 3} potential energy surface using a time-dependent wave packet method. The agreement between calculated and measured rate coefficients is significantly improved over previous work. More importantly, the experimentally observed negative temperature dependence of the rate coefficients is for the first time rigorously reproduced theoretically. This negative temperature dependence can be attributed to the absence in the new potential energy surface of a submerged “reef” structure, which was present in all previous potential energy surfaces. In addition, contributions of rotational excited states of the diatomic reactant further accentuate the negative temperature dependence.

Authors:
;  [1];  [2]; ;  [3];  [4];  [5]
  1. State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning 116023 (China)
  2. (China)
  3. Department of Chemistry and Chemical Biology, University of New Mexico, Albuquerque, New Mexico 87131 (United States)
  4. Institute of Theoretical and Computational Chemistry, Key Laboratory of Mesoscopic Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093 (China)
  5. Department of Chemistry, Missouri University of Science and Technology, Rolla, Missouri 65409 (United States)
Publication Date:
OSTI Identifier:
22419815
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Chemical Physics; Journal Volume: 141; Journal Issue: 8; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; EXCITED STATES; ISOTOPIC EXCHANGE; KINETICS; POTENTIAL ENERGY; SURFACES; TEMPERATURE DEPENDENCE; TIME DEPENDENCE; WAVE PACKETS

Citation Formats

Li, Yaqin, Sun, Zhigang, E-mail: zsun@dicp.ac.cn, E-mail: dawesr@mst.edu, E-mail: hguo@unm.edu, Center for Advanced Chemical Physics, University of Science and Technology of China, 96 Jinzhai Road, Hefei 230026, Jiang, Bin, Guo, Hua, E-mail: zsun@dicp.ac.cn, E-mail: dawesr@mst.edu, E-mail: hguo@unm.edu, Xie, Daiqian, and Dawes, Richard, E-mail: zsun@dicp.ac.cn, E-mail: dawesr@mst.edu, E-mail: hguo@unm.edu. Communication: Rigorous quantum dynamics of O + O{sub 2} exchange reactions on an ab initio potential energy surface substantiate the negative temperature dependence of rate coefficients. United States: N. p., 2014. Web. doi:10.1063/1.4894069.
Li, Yaqin, Sun, Zhigang, E-mail: zsun@dicp.ac.cn, E-mail: dawesr@mst.edu, E-mail: hguo@unm.edu, Center for Advanced Chemical Physics, University of Science and Technology of China, 96 Jinzhai Road, Hefei 230026, Jiang, Bin, Guo, Hua, E-mail: zsun@dicp.ac.cn, E-mail: dawesr@mst.edu, E-mail: hguo@unm.edu, Xie, Daiqian, & Dawes, Richard, E-mail: zsun@dicp.ac.cn, E-mail: dawesr@mst.edu, E-mail: hguo@unm.edu. Communication: Rigorous quantum dynamics of O + O{sub 2} exchange reactions on an ab initio potential energy surface substantiate the negative temperature dependence of rate coefficients. United States. doi:10.1063/1.4894069.
Li, Yaqin, Sun, Zhigang, E-mail: zsun@dicp.ac.cn, E-mail: dawesr@mst.edu, E-mail: hguo@unm.edu, Center for Advanced Chemical Physics, University of Science and Technology of China, 96 Jinzhai Road, Hefei 230026, Jiang, Bin, Guo, Hua, E-mail: zsun@dicp.ac.cn, E-mail: dawesr@mst.edu, E-mail: hguo@unm.edu, Xie, Daiqian, and Dawes, Richard, E-mail: zsun@dicp.ac.cn, E-mail: dawesr@mst.edu, E-mail: hguo@unm.edu. Thu . "Communication: Rigorous quantum dynamics of O + O{sub 2} exchange reactions on an ab initio potential energy surface substantiate the negative temperature dependence of rate coefficients". United States. doi:10.1063/1.4894069.
@article{osti_22419815,
title = {Communication: Rigorous quantum dynamics of O + O{sub 2} exchange reactions on an ab initio potential energy surface substantiate the negative temperature dependence of rate coefficients},
author = {Li, Yaqin and Sun, Zhigang, E-mail: zsun@dicp.ac.cn, E-mail: dawesr@mst.edu, E-mail: hguo@unm.edu and Center for Advanced Chemical Physics, University of Science and Technology of China, 96 Jinzhai Road, Hefei 230026 and Jiang, Bin and Guo, Hua, E-mail: zsun@dicp.ac.cn, E-mail: dawesr@mst.edu, E-mail: hguo@unm.edu and Xie, Daiqian and Dawes, Richard, E-mail: zsun@dicp.ac.cn, E-mail: dawesr@mst.edu, E-mail: hguo@unm.edu},
abstractNote = {The kinetics and dynamics of several O + O{sub 2} isotope exchange reactions have been investigated on a recently determined accurate global O{sub 3} potential energy surface using a time-dependent wave packet method. The agreement between calculated and measured rate coefficients is significantly improved over previous work. More importantly, the experimentally observed negative temperature dependence of the rate coefficients is for the first time rigorously reproduced theoretically. This negative temperature dependence can be attributed to the absence in the new potential energy surface of a submerged “reef” structure, which was present in all previous potential energy surfaces. In addition, contributions of rotational excited states of the diatomic reactant further accentuate the negative temperature dependence.},
doi = {10.1063/1.4894069},
journal = {Journal of Chemical Physics},
number = 8,
volume = 141,
place = {United States},
year = {Thu Aug 28 00:00:00 EDT 2014},
month = {Thu Aug 28 00:00:00 EDT 2014}
}
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