Decoupling scheme for a semiclassical treatment of electronic transitions in atom--diatom collisions: Real-valued trajectories and local analytic continuation

Journal Article · Thu Jul 01 04:00:00 EDT 1976 · J. Chem. Phys.; (United States)

DOI:https://doi.org/10.1063/1.432744· OSTI ID:7348925

Komornicki, A; George, T F; Morokuma, K

The semiclassical theory of electronically nonadiabatic transitions in atom--diatom collisions is modified by the introduction of a decoupling approach to the nuclear dynamics. The probability of switching surfaces is calculated locally by integrating in the complex plane over a nuclear coordinate which couples most strongly to the electronic transition. A substantial computational simplification results when this approach is implemented. The power of the method lies in the fact that the potential energy surfaces need be analytically continued locally rather than globally. Thus the trajectories can be maintained on the real axis except for the one point where the surfaces are switched. Computational results are presented and discussed for two model collinear nonreactive systems, F+H/sub 2/ and Br+H/sub 2/. It is shown that when the possibility of an E--V resonant energy transfer exists, the vibrational as well as the electronic degrees of freedom must be treated quantum mechanically. (AIP)

• Research Organization: Department of Chemistry, The University of Rochester, Rochester, New York 14627
• OSTI ID: 7348925
• Journal Information: J. Chem. Phys.; (United States), Journal Name: J. Chem. Phys.; (United States) Vol. 65:1; ISSN JCPSA
• Country of Publication: United States
• Language: English

Related Subjects

640304* -- Atomic
Molecular & Chemical Physics-- Collision Phenomena
74 ATOMIC AND MOLECULAR PHYSICS
ATOM COLLISIONS
ATOM-MOLECULE COLLISIONS
COLLISIONS
CRYOGENIC FLUIDS
ELEMENTS
ENERGY TRANSFER
ENERGY-LEVEL TRANSITIONS
EXCITATION
FLUIDS
FLUORINE
HALOGENS
HYDROGEN
MOLECULE COLLISIONS
NONMETALS