Quasiclassical Differential Cross Sections for Reactive Scattering of H + H2 on Leps and Porter-Karplus Potential Surfaces
Abstract
The determination of the reactive differential cross section I(θ) from quasiclassical trajectory calculations has been reviewed by Truhlar and Muckerman.1 Two procedures have been used in the past to display the cross section. The first is the histogram method. One serious problem with this method is that a continuous function I(θ) is being approximated by a discontinous histogram. In addition, there are problems with choosing the locations and widths of the angular bins.2 The second procedure is to expand I(θ) in a series of Legendre polynomials.3-5 However, there are also problems with this method. First, it isn’t certain at what point to truncate the series to minimize the uncertainty in I(θ). In addition, there is no simple expression for the uncertainty in the differential cross section. Because of these problems only a small number of comparisons of differential cross sections for different potential energy surfaces have been made.
Keywords
Potential Energy Surface Differential Cross Section Reactive Trajectory Fourier Sine Series Quasiclassical TrajectoryPreview
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References
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