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Title: Wave packet and statistical quantum calculations for the He + NeH{sup +} → HeH{sup +} + Ne reaction on the ground electronic state

Abstract

A real wave packet based time-dependent method and a statistical quantum method have been used to study the He + NeH{sup +} (v, j) reaction with the reactant in various ro-vibrational states, on a recently calculated ab initio ground state potential energy surface. Both the wave packet and statistical quantum calculations were carried out within the centrifugal sudden approximation as well as using the exact Hamiltonian. Quantum reaction probabilities exhibit dense oscillatory pattern for smaller total angular momentum values, which is a signature of resonances in a complex forming mechanism for the title reaction. Significant differences, found between exact and approximate quantum reaction cross sections, highlight the importance of inclusion of Coriolis coupling in the calculations. Statistical results are in fairly good agreement with the exact quantum results, for ground ro-vibrational states of the reactant. Vibrational excitation greatly enhances the reaction cross sections, whereas rotational excitation has relatively small effect on the reaction. The nature of the reaction cross section curves is dependent on the initial vibrational state of the reactant and is typical of a late barrier type potential energy profile.

Authors:
;  [1]; ;  [2]
  1. Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati 781039 (India)
  2. Instituto de Física Fundamental, C.S.I.C., Serrano 123, Madrid 28006 (Spain)
Publication Date:
OSTI Identifier:
22308404
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Chemical Physics; Journal Volume: 141; Journal Issue: 11; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
74 ATOMIC AND MOLECULAR PHYSICS; CROSS SECTIONS; EXCITATION; GROUND STATES; HAMILTONIANS; INCLUSIONS; POTENTIAL ENERGY; SUDDEN APPROXIMATION; VIBRATIONAL STATES; WAVE PACKETS

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. Wave packet and statistical quantum calculations for the He + NeH{sup +} → HeH{sup +} + Ne reaction on the ground electronic state. United States: N. p., 2014. Web. doi:10.1063/1.4895567.
Koner, Debasish, Panda, Aditya N., E-mail: adi07@iitg.ernet.in, Barrios, Lizandra, & González-Lezana, Tomás, E-mail: t.gonzalez.lezana@csic.es. Wave packet and statistical quantum calculations for the He + NeH{sup +} → HeH{sup +} + Ne reaction on the ground electronic state. United States. doi:10.1063/1.4895567.
Koner, Debasish, Panda, Aditya N., E-mail: adi07@iitg.ernet.in, Barrios, Lizandra, and González-Lezana, Tomás, E-mail: t.gonzalez.lezana@csic.es. 2014. "Wave packet and statistical quantum calculations for the He + NeH{sup +} → HeH{sup +} + Ne reaction on the ground electronic state". United States. doi:10.1063/1.4895567.
@article{osti_22308404,
title = {Wave packet and statistical quantum calculations for the He + NeH{sup +} → HeH{sup +} + Ne reaction on the ground electronic state},
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 = {A real wave packet based time-dependent method and a statistical quantum method have been used to study the He + NeH{sup +} (v, j) reaction with the reactant in various ro-vibrational states, on a recently calculated ab initio ground state potential energy surface. Both the wave packet and statistical quantum calculations were carried out within the centrifugal sudden approximation as well as using the exact Hamiltonian. Quantum reaction probabilities exhibit dense oscillatory pattern for smaller total angular momentum values, which is a signature of resonances in a complex forming mechanism for the title reaction. Significant differences, found between exact and approximate quantum reaction cross sections, highlight the importance of inclusion of Coriolis coupling in the calculations. Statistical results are in fairly good agreement with the exact quantum results, for ground ro-vibrational states of the reactant. Vibrational excitation greatly enhances the reaction cross sections, whereas rotational excitation has relatively small effect on the reaction. The nature of the reaction cross section curves is dependent on the initial vibrational state of the reactant and is typical of a late barrier type potential energy profile.},
doi = {10.1063/1.4895567},
journal = {Journal of Chemical Physics},
number = 11,
volume = 141,
place = {United States},
year = 2014,
month = 9
}
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