General Potential-Energy Function for Exchange Reactions

Abstract

A general potential-energy function for linear triatomic systems has been developed for use in connection with reaction kinetics calculations. The function is a generalization of the Morse function with a sufficient number of adjustable parameters to permit arbitrary fixing of the location and curvatures of the saddle point of the potential energy surface. The function reduces, of course, to the Morse function when one of the atoms is infinitely distant from the other two. Since the characteristics of the saddle region are adjustable, the function is particularly useful in connection with computations designed to test the effect of different shapes of potential energy surfaces upon reaction probabilities. The function is most readily used for symmetric reactions, but it can be further generalized to cover unsymmetric cases.