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Title: Semiclassical Wigner theory of photodissociation in three dimensions: Shedding light on its basis

The semiclassical Wigner theory (SCWT) of photodissociation dynamics, initially proposed by Brown and Heller [J. Chem. Phys. 75, 186 (1981)] in order to describe state distributions in the products of direct collinear photodissociations, was recently extended to realistic three-dimensional triatomic processes of the same type [Arbelo-González et al., Phys. Chem. Chem. Phys. 15, 9994 (2013)]. The resulting approach, which takes into account rotational motions in addition to vibrational and translational ones, was applied to a triatomic-like model of methyl iodide photodissociation and its predictions were found to be in nearly quantitative agreement with rigorous quantum results, but at a much lower computational cost, making thereby SCWT a potential tool for the study of polyatomic reaction dynamics. Here, we analyse the main reasons for this agreement by means of an elementary model of fragmentation explicitly dealing with the rotational motion only. We show that our formulation of SCWT makes it a semiclassical approximation to an approximate planar quantum treatment of the dynamics, both of sufficient quality for the whole treatment to be satisfying.
Authors:
 [1] ;  [2] ;  [2] ;  [3] ;  [2] ;  [4]
  1. Max Planck Institut für Kohlenforschung, Mülheim an der Ruhr (Germany)
  2. (France)
  3. CNRS, Institut des Sciences Moléculaires, UMR 5255, 33405 Talence (France)
  4. Instituto de Física Fundamental, C.S.I.C., Serrano 123, 28006 Madrid (Spain)
Publication Date:
OSTI Identifier:
22415600
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Chemical Physics; Journal Volume: 142; Journal Issue: 13; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; DISSOCIATION; FRAGMENTATION; METHYL IODIDE; PHOTOLYSIS; SEMICLASSICAL APPROXIMATION; THREE-DIMENSIONAL CALCULATIONS; VISIBLE RADIATION; WIGNER THEORY