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Title: The predissociation mechanism of the B(tilde sign) {sup 2}A{sup '} state of HCO via the conical intersection with the X(tilde sign) {sup 2}A{sup '} state

Abstract

We use large-scale multiconfiguration self-consistent field/configuration interaction calculations to characterize the predissociation mechanism of the B(tilde sign) {sup 2}A{sup '} state of HCO through conical intersection with the X(tilde sign) {sup 2}A{sup '} ground state. We locate two regions of intersection: the first represents a highly bent HCO that is 8 kcal/mol energetically lower than the B(tilde sign) state minimum, with a barrier height of 26 kcal/mol. Energy points on the B(tilde sign) {sup 2}A{sup '} potential surface connecting these extrema were also calculated. This region emphatically illustrates the feasibility of a nonradiative decay mechanism consistent with latest experimental findings of purely vibronic coupling mechanism. The second region of intersection represents a confluence of three linear {sup 2}{sigma}{sup +}-{sup 2}{pi} states crossings, 53 kcal/mol below the B(tilde sign) state minimum. A barrier about 21 kcal/mol above the B(tilde sign) state equilibrium structure is located and assigned to the entrance channel of H-CO({sup 3}{pi}). (c) 2000 American Institute of Physics.

Authors:
 [1]
  1. University of California, Lawrence Livermore National Laboratory, Energetic Materials Center, P.O. Box 808, L-282, Livermore, California 94551 (United States)
Publication Date:
OSTI Identifier:
20216376
Resource Type:
Journal Article
Journal Name:
Journal of Chemical Physics
Additional Journal Information:
Journal Volume: 112; Journal Issue: 20; Other Information: PBD: 22 May 2000; Journal ID: ISSN 0021-9606
Country of Publication:
United States
Language:
English
Subject:
74 ATOMIC AND MOLECULAR PHYSICS; FORMYL RADICALS; PREDISSOCIATION; ELECTRONIC STRUCTURE; RADIATIONLESS DECAY; COMBUSTION; CONFIGURATION INTERACTION; THEORETICAL DATA

Citation Formats

Manaa, M. Riad. The predissociation mechanism of the B(tilde sign) {sup 2}A{sup '} state of HCO via the conical intersection with the X(tilde sign) {sup 2}A{sup '} state. United States: N. p., 2000. Web. doi:10.1063/1.481533.
Manaa, M. Riad. The predissociation mechanism of the B(tilde sign) {sup 2}A{sup '} state of HCO via the conical intersection with the X(tilde sign) {sup 2}A{sup '} state. United States. doi:10.1063/1.481533.
Manaa, M. Riad. Mon . "The predissociation mechanism of the B(tilde sign) {sup 2}A{sup '} state of HCO via the conical intersection with the X(tilde sign) {sup 2}A{sup '} state". United States. doi:10.1063/1.481533.
@article{osti_20216376,
title = {The predissociation mechanism of the B(tilde sign) {sup 2}A{sup '} state of HCO via the conical intersection with the X(tilde sign) {sup 2}A{sup '} state},
author = {Manaa, M. Riad},
abstractNote = {We use large-scale multiconfiguration self-consistent field/configuration interaction calculations to characterize the predissociation mechanism of the B(tilde sign) {sup 2}A{sup '} state of HCO through conical intersection with the X(tilde sign) {sup 2}A{sup '} ground state. We locate two regions of intersection: the first represents a highly bent HCO that is 8 kcal/mol energetically lower than the B(tilde sign) state minimum, with a barrier height of 26 kcal/mol. Energy points on the B(tilde sign) {sup 2}A{sup '} potential surface connecting these extrema were also calculated. This region emphatically illustrates the feasibility of a nonradiative decay mechanism consistent with latest experimental findings of purely vibronic coupling mechanism. The second region of intersection represents a confluence of three linear {sup 2}{sigma}{sup +}-{sup 2}{pi} states crossings, 53 kcal/mol below the B(tilde sign) state minimum. A barrier about 21 kcal/mol above the B(tilde sign) state equilibrium structure is located and assigned to the entrance channel of H-CO({sup 3}{pi}). (c) 2000 American Institute of Physics.},
doi = {10.1063/1.481533},
journal = {Journal of Chemical Physics},
issn = {0021-9606},
number = 20,
volume = 112,
place = {United States},
year = {2000},
month = {5}
}