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The Journal of Chemical Physics

Semiclassical dynamics of nonadiabatic transitions in discrete-state systems using spin coherent-state path integrals

A. Lücke, Chi H. Mak, Jürgen T. Stockburger

Published Dec 22, 1999• 13 citations
Publisher

Abstract

We present a semiclassical method for simulating the dynamics of nonadiabatic transitions in a discrete-state quantum system coupled to a bath of explicit continuous coordinates. This method employs a coherent-state formulation of the path integrals for the discrete system whose dynamics is described by spin operators. This spin coherent-state formulation allows the discrete system to be mapped onto a continuous coordinate. Stationary approximations of the resulting coherent-state path integrals of the system plus bath lead to quasiclassical equations of motion which can be solved numerically by direct integration. This algorithm reduces the problem to a number of simple classical trajectory calculations and does not require calculating any fluctuation determinants.

DOI
10.1063/1.480448

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