Calculation of the energies, geometries, and vibration frequencies of alkali halide dimers

The potential energy surfaces for a number of alkali halide dimer molecules were calculated from an electron gas model. These results were used to predict binding energies, equilibrium geometries, and vibration frequencies for M ₂X₂ molecules, with M=Li, Na, K, and Rb, and X=F, Cl, and Br. The accuracy of these a priori results (no adjustable parameters) is comparable to that of previous semiempirical models with several adjustable parameters.