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Title: Scattering study of the Ne + NeH{sup +}(v{sub 0} = 0, j{sub 0} = 0) → NeH{sup +} + Ne reaction on an ab initio based analytical potential energy surface

Abstract

Initial state selected dynamics of the Ne + NeH{sup +}(v{sub 0} = 0, j{sub 0} = 0) → NeH{sup +} + Ne reaction is investigated by quantum and statistical quantum mechanical (SQM) methods on the ground electronic state. The three-body ab initio energies on a set of suitably chosen grid points have been computed at CCSD(T)/aug-cc-PVQZ level and analytically fitted. The fitting of the diatomic potentials, computed at the same level of theory, is performed by spline interpolation. A collinear [NeHNe]{sup +} structure lying 0.72 eV below the Ne + NeH{sup +} asymptote is found to be the most stable geometry for this system. Energies of low lying vibrational states have been computed for this stable complex. Reaction probabilities obtained from quantum calculations exhibit dense oscillatory structures, particularly in the low energy region and these get partially washed out in the integral cross section results. SQM predictions are devoid of oscillatory structures and remain close to 0.5 after the rise at the threshold thus giving a crude average description of the quantum probabilities. Statistical cross sections and rate constants are nevertheless in sufficiently good agreement with the quantum results to suggest an important role of a complex-forming dynamics for themore » title reaction.« less

Authors:
;  [1]; ;  [2]
  1. Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati 781039 (India)
  2. IFF-CSIC, Instituto de Física Fundamental, CSIC, Serrano 123, Madrid 28006 (Spain)
Publication Date:
OSTI Identifier:
22493664
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Chemical Physics; Journal Volume: 144; Journal Issue: 3; Other Information: (c) 2016 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
74 ATOMIC AND MOLECULAR PHYSICS; COMPLEXES; EV RANGE; INTEGRAL CROSS SECTIONS; INTERPOLATION; ION-ATOM COLLISIONS; NEON; NEON HYDRIDES; POTENTIAL ENERGY; POTENTIALS; PROBABILITY; QUANTUM MECHANICS; REACTION KINETICS; SCATTERING; SURFACES; THREE-BODY PROBLEM; VIBRATIONAL STATES

Citation Formats

Koner, Debasish, Panda, Aditya N., E-mail: adi07@iitg.ernet.in, Barrios, Lizandra, and González-Lezana, Tomás, E-mail: t.gonzalez.lezana@csic.es. Scattering study of the Ne + NeH{sup +}(v{sub 0} = 0, j{sub 0} = 0) → NeH{sup +} + Ne reaction on an ab initio based analytical potential energy surface. United States: N. p., 2016. Web. doi:10.1063/1.4939952.
Koner, Debasish, Panda, Aditya N., E-mail: adi07@iitg.ernet.in, Barrios, Lizandra, & González-Lezana, Tomás, E-mail: t.gonzalez.lezana@csic.es. Scattering study of the Ne + NeH{sup +}(v{sub 0} = 0, j{sub 0} = 0) → NeH{sup +} + Ne reaction on an ab initio based analytical potential energy surface. United States. doi:10.1063/1.4939952.
Koner, Debasish, Panda, Aditya N., E-mail: adi07@iitg.ernet.in, Barrios, Lizandra, and González-Lezana, Tomás, E-mail: t.gonzalez.lezana@csic.es. 2016. "Scattering study of the Ne + NeH{sup +}(v{sub 0} = 0, j{sub 0} = 0) → NeH{sup +} + Ne reaction on an ab initio based analytical potential energy surface". United States. doi:10.1063/1.4939952.
@article{osti_22493664,
title = {Scattering study of the Ne + NeH{sup +}(v{sub 0} = 0, j{sub 0} = 0) → NeH{sup +} + Ne reaction on an ab initio based analytical potential energy surface},
author = {Koner, Debasish and Panda, Aditya N., E-mail: adi07@iitg.ernet.in and Barrios, Lizandra and González-Lezana, Tomás, E-mail: t.gonzalez.lezana@csic.es},
abstractNote = {Initial state selected dynamics of the Ne + NeH{sup +}(v{sub 0} = 0, j{sub 0} = 0) → NeH{sup +} + Ne reaction is investigated by quantum and statistical quantum mechanical (SQM) methods on the ground electronic state. The three-body ab initio energies on a set of suitably chosen grid points have been computed at CCSD(T)/aug-cc-PVQZ level and analytically fitted. The fitting of the diatomic potentials, computed at the same level of theory, is performed by spline interpolation. A collinear [NeHNe]{sup +} structure lying 0.72 eV below the Ne + NeH{sup +} asymptote is found to be the most stable geometry for this system. Energies of low lying vibrational states have been computed for this stable complex. Reaction probabilities obtained from quantum calculations exhibit dense oscillatory structures, particularly in the low energy region and these get partially washed out in the integral cross section results. SQM predictions are devoid of oscillatory structures and remain close to 0.5 after the rise at the threshold thus giving a crude average description of the quantum probabilities. Statistical cross sections and rate constants are nevertheless in sufficiently good agreement with the quantum results to suggest an important role of a complex-forming dynamics for the title reaction.},
doi = {10.1063/1.4939952},
journal = {Journal of Chemical Physics},
number = 3,
volume = 144,
place = {United States},
year = 2016,
month = 1
}
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