Comparison of variational transition state theory and quantum sudden calculations of threedimensional rate coefficients for the reactions D(H)+BrH > DBr(HBr)+H
Abstract
We calculate rate coefficients for the threedimensional reactions H+BrH → HBr+H and D+BrH → DBr+H using two different dynamical methods but with the same potential energy surface. One method is a threedimensional quantum mechanical technique in which the energy sudden approximation is used for the entrance reaction channel and the centrifugal sudden approximation is applied to the exit reaction channel. The second method is improved canonical variational transition state theory with smallcurvaturetunneling semiclassical adiabatic groundstate transmission coefficients. The potential energy surface is an empirically adjusted diatomicsinmolecules surface which has a very narrow barrier to reaction. The rate coefficients predicted by the two very different dynamical theories are in excellent agreement—they differ by less than 20% over the temperature range from 150 to 500 K.
 Publication:

Journal of Chemical Physics
 Pub Date:
 January 1983
 DOI:
 10.1063/1.444829
 Bibcode:
 1983JChPh..78..777C