Quasiclassical determination of reaction probabilities as a function of the total angular momentum.

Departamento de Química Física, Facultad de Química, Universidad Complutense, 28040 Madrid, Spain.
The Journal of Chemical Physics (Impact Factor: 3.12). 10/2005; 123(9):94101. DOI: 10.1063/1.2009739
Source: PubMed

ABSTRACT This article presents a quasiclassical trajectory (QCT) method to determine the reaction probability as a function of the total angular momentum J for any given value of the initial rotational angular momentum j. The proposed method is based on a discrete sampling of the total and orbital angular momenta for each trajectory and on the development of equations that have a clear counterpart in the quantum-mechanical (QM) case. The reliability of the method is illustrated by comparing QCT and time-dependent wave-packet QM results for the H+D(2)(upsilon=0,j=4,10) reaction. The small discrepancies between both sets of calculations, when they exist, indicate some genuine quantum effects. In addition, a procedure to extract the reaction probabilities as a function of J when trajectories are calculated in the usual way using a continuous distribution of impact parameters is also described.

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