A criterion for the applicability of the method of diatomics-in-molecules to potential surface calculations. I. Selection of the DIM basis

Abstract

A self‐consistency criterion is applied to the method of diatomics‐in‐molecules in order to determine, in a resasonable manner, the minimum DIM polyatomic basis set needed to describe a given state of a polyatomic system. The method requires only the calculation of overlap integrals of the DIM basis functions with ab initio wave functions for the diatomic fragment states. The procedure is applied to the reaction Be+HF→BeF+H (¹A′ ground state), for which extensive DIM model calculations are available.