Reactive modes in condensed phase reactions

Abstract

The rate constant k for condensed phase chemical reactions is found when a saddle point normal mode analysis holds and when the dynamic solvent forces are of the generalized Langevin type. If the reactive and nonreactive modes are uncoupled, the deviation of k from its transition state value ktst is governed by the nonadiabatic friction on the reactive mode. In the more typical case where the modes are coupled k/ktst is governed by an effective nonadiabatic reactive mode friction which completely accounts for intramode coupling. Some simple illustrations of mode coupling effects on k are given.