Rate theory and non-RRKM quantum dynamics described by local random matrix models

Abstract

A model of the quantum return dynamics based on a scaling perspective on energy flow and localization of eigenstates is used to describe corrections to the RRKM theory of unimolecular dissociation. The scaling perspective addresses systems described by a local random matrix model for the Hamiltonian. The effect of the dynamics upon the degree of electronic adiabaticity of the reaction is also discussed. It is found that at the localization transition the reaction proceeds as if through a number of channels of order unity, giving a rate which is more likely to be electronically adiabatic and is far slower than the RRKM prediction for the adiabatic rate.