Quantum reactive scattering: Diabatic approach to the dynamics of chemical reactions

Journal Article · Mon Aug 15 04:00:00 EDT 1994 · Journal of Chemical Physics; (United States)

DOI:https://doi.org/10.1063/1.467598· OSTI ID:7084682

Shin, S; Light, J C ^[1]

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1. Department of Chemistry and The James Franck Institute, University of Chicago, Chicago, Illinois 60637 (United States)

We present a diabatic approach to the dynamics of electronically adiabatic chemical reactions. A method is proposed for constructing diabatic surfaces from a single adiabatic potential surface. By using diabatic surfaces we can choose natural coordinate systems for both the reactant and product arrangements. The diabatic approach can be easily adapted to exact quantum mechanical calculations based on variational scattering formulations. The square integrable basis functions are obtained by diagonalizing the total Hamiltonian matrix which is constructed from the separate eigenfunctions on the reactant and product diabatic surfaces. Applications to one-dimensional barrier problems and the collinear H+H[sub 2][r arrow]H[sub 2]+H reaction demonstrate the feasibility of the diabatic approach. At low total energies, reaction probabilities for adiabatic reactions can be reproduced by the present method. Moderately accurate results can be obtained at high total energies for the collinear H+H[sub 2][r arrow]H[sub 2]+H reaction, which may be improved by the optimal construction of diabatic surfaces.

• DOE Contract Number: FG02-87ER13679
• OSTI ID: 7084682
• Journal Information: Journal of Chemical Physics; (United States), Journal Name: Journal of Chemical Physics; (United States) Vol. 101:4; ISSN JCPSA6; ISSN 0021-9606
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
ADIABATIC PROCESSES
ATOM COLLISIONS
ATOM-MOLECULE COLLISIONS
CALCULATION METHODS
CHEMICAL REACTION KINETICS
CHEMICAL REACTIONS
COLLISIONS
COORDINATES
DIABATIC APPROXIMATION
ELEMENTS
ENERGY
HAMILTONIANS
HYDROGEN
KINETICS
MATHEMATICAL OPERATORS
MATRICES
MOLECULE COLLISIONS
NONMETALS
ONE-DIMENSIONAL CALCULATIONS
POTENTIAL ENERGY
POTENTIALS
PROBABILITY
QUANTUM OPERATORS
REACTION KINETICS