Electronic States of Molecules. II. Calculations of the Potential-Energy Curve and Molecular Constants of LiH(X 1Σ+)

Abstract

The self-consistent-field molecular-orbital method in the LCAO (linear combination of atomic orbitals) approximation is applied to the ground state of LiH at a number of internuclear distances (R) for the calculation of the potential energy (PE) curve. In this calculation both the LCAO coefficients and the oribital exponents of 1s, 2s, and 2p AO's of Li and H atoms are optimized. The computed wavefunctions are further subjected to a configuration-interaction treatment using 41 configurations at each R to obtain a PE curve. The PE curves, computed with and without configuration-interaction treatment, have been used in the solution of the radial Schrödinger equation to compute the molecular constants ωe, ωexe, Be, αe, Re, and De. The dipole moment computed at Re shows Li+H– polarity. The computed results are compared with the experimental data.