Adiabatic theory of chemical reactions

Abstract

The recent results of Morokuma, Eu, and Karplus on what collision cross sections and reaction probabilities are implied by the usual transition state theory of reactions are examined in terms of the adiabatic justification of transition state theory. Eliason and Hirschfelder's and Marcus's definition of a generalized activated complex and the theory of adiabatic reactions are used to remove the inconsistencies and divergences Morokuma et al. found in the transition state theory. It is found that the usual transition state theory is not exactly equivalent to the adiabatic theory of reactions. The corrected transition state theory is equivalent to the adiabatic theory at low temperatures for the simple barrier-potential type of reactions, e.g., H+H 2.