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Title: Ab initio and analytical intermolecular potential for ClO-H2O

Abstract

In recent years, the ClO free radical has been found to play an important role in the ozone removal processes in the atmosphere. In this work, we present a Potential Energy Surface (PES) Scan of the ClO•H2O system with high-level ab initio methods. Because of the existence of low-lying excited states of the ClO•H2O complex, and their potential impact on the chemical behavior of the ClO radical in the atmosphere, we perform a PES scan at CCSD(T)/aug-cc-pVTZ level of both the first excited and ground states in order to model the physics of the unpaired electron in the ClO radical. Analytical potentials for both ground and excited states, with internal molecular coordinates held fixed, were built based on a Thole Type Model. The two minima of the ClO•H2O complex are recovered by the analytical potential. This work was supported by the Office of Basic Energy Sciences of the Department of Energy, in part by the Chemical Sciences program and in part by the Engineering and Geosciences Division. The Pacific Northwest National Laboratory is operated by Battelle for the U.S. Department of Energy.

Authors:
; ; ;
Publication Date:
Research Org.:
Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
908940
Report Number(s):
PNNL-SA-52366
Journal ID: ISSN 0021-9606; JCPSA6; KC0301020; TRN: US200722%%823
DOE Contract Number:
AC05-76RL01830
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Chemical Physics, 126(11):146-155; Journal Volume: 126; Journal Issue: 11
Country of Publication:
United States
Language:
English
Subject:
54 ENVIRONMENTAL SCIENCES; CHLORINE OXIDES; HYDRATES; EXCITED STATES; GROUND STATES; OZONE; POTENTIAL ENERGY; RADICALS; REMOVAL; ATMOSPHERIC CHEMISTRY; C1O-H2O system; ab initio; ozone removal process

Citation Formats

Du, Shiyu, Francisco, Joseph S., Schenter, Gregory K., and Garrett, Bruce C. Ab initio and analytical intermolecular potential for ClO-H2O. United States: N. p., 2007. Web. doi:10.1063/1.2566537.
Du, Shiyu, Francisco, Joseph S., Schenter, Gregory K., & Garrett, Bruce C. Ab initio and analytical intermolecular potential for ClO-H2O. United States. doi:10.1063/1.2566537.
Du, Shiyu, Francisco, Joseph S., Schenter, Gregory K., and Garrett, Bruce C. Mon . "Ab initio and analytical intermolecular potential for ClO-H2O". United States. doi:10.1063/1.2566537.
@article{osti_908940,
title = {Ab initio and analytical intermolecular potential for ClO-H2O},
author = {Du, Shiyu and Francisco, Joseph S. and Schenter, Gregory K. and Garrett, Bruce C.},
abstractNote = {In recent years, the ClO free radical has been found to play an important role in the ozone removal processes in the atmosphere. In this work, we present a Potential Energy Surface (PES) Scan of the ClO•H2O system with high-level ab initio methods. Because of the existence of low-lying excited states of the ClO•H2O complex, and their potential impact on the chemical behavior of the ClO radical in the atmosphere, we perform a PES scan at CCSD(T)/aug-cc-pVTZ level of both the first excited and ground states in order to model the physics of the unpaired electron in the ClO radical. Analytical potentials for both ground and excited states, with internal molecular coordinates held fixed, were built based on a Thole Type Model. The two minima of the ClO•H2O complex are recovered by the analytical potential. This work was supported by the Office of Basic Energy Sciences of the Department of Energy, in part by the Chemical Sciences program and in part by the Engineering and Geosciences Division. The Pacific Northwest National Laboratory is operated by Battelle for the U.S. Department of Energy.},
doi = {10.1063/1.2566537},
journal = {Journal of Chemical Physics, 126(11):146-155},
number = 11,
volume = 126,
place = {United States},
year = {Mon Mar 19 00:00:00 EDT 2007},
month = {Mon Mar 19 00:00:00 EDT 2007}
}
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