Multichannel distorted wave Born approximation for reactive scattering
Previous applications of the distorted wave Born approximation (DWBA) to reactive scattering have often given reasonably good relative cross sections, i.e., angular distributions, product state distributions, etc.: but absolute reactive cross sections have been poor. It is argued in this paper, however, that the DWBA for reactive scattering should be accurate if (1) the reaction probability is sufficiently small (as it is, e.g., in the threshold region of a reaction) and (2) the nonreactive scattering is described sufficiently accurately. To describe the nonreactive scattering ''sufficiently accurately'' this paper utilizes a nonreactive coupled-channel scattering wave function for distorted waves in the DWBA. Application to a standard test problem (collinear H+H/sub 2/) shows this multichannel DWBA indeed to be extremely accurate if the reaction probability is no larger than 0.1 and if approx.3 to 4 vibrational states are included in the nonreactive coupled-channel expansion. This approach thus provides an excellent description of the threshold region of a reaction which has an activation barrier.
- Research Organization:
- Department of Chemistry and Materials and Molecular Research Division of Lawrence Berkeley Laboratory, University of California, Berkeley, California 94720
- OSTI ID:
- 6517088
- Journal Information:
- J. Chem. Phys.; (United States), Journal Name: J. Chem. Phys.; (United States) Vol. 78:5; ISSN JCPSA
- Country of Publication:
- United States
- Language:
- English
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