Representation of potential energy surfaces by discrete polynomials: proton transfer in malonaldehyde†
Abstract
A new method for the expansion of potential energy surfaces has been developed exploiting the peculiar properties of Hahn polynomials, a class of orthogonal polynomials of a discrete variable which generalize 3j
vector coupling coefficients of angular momentum algebra. The method has been tested for the Hénon–Heiles potential, a typical model for coupled oscillators, and applied to the representation of the potential energy surface of