Welcome to the new version of CaltechAUTHORS. Login is currently restricted to library staff. If you notice any issues, please email coda@library.caltech.edu
Published February 19, 1988 | public
Journal Article

On the theory of the state distribution of the reaction products and rates of unimolecular dissociations

Abstract

A recent variational implementation of RRKM theory, plus an additional dynamical assumption, is used to calculate the distribution of quantum states of reaction products of unimolecular dissociations. It is assumed that the "conserved" modes of the molecule are vibrationally adiabatic after passage through the transition state region, but that the "transitional modes" are non-adiabatic until the "loose transition state" region is reached. The rate constants k_(EJ) themselves are those of RRKM theory, but, for energies below those needed to yield vibrationally excited products, the phase space theory expression (PST) is obtained for the distribution of rotational states of the products. The product state distribution differs from that of PST when the energy is sufficient to permit product vibrational excitation. The unimolecular reactions considered are those for which there is no potential energy barrier for the reverse reaction (recombination).

Additional Information

© 1988 Published by Elsevier B.V. Received 23 October 1987; in final form 4 January 1988. It is a pleasure to acknowledge the support of this research by the National Science Foundation. The present paper was prompted by participation in a symposium at Grainau, organized by Ed Schlag and Martin Quack, and I am indebted to them for having arranged such an interesting conference. I should also like to thank Steve Klippenstein for his perceptive comments. This is contribution No. 7684 from the Department of Chemistry at Caltech.

Additional details

Created:
August 19, 2023
Modified:
October 23, 2023