Electron Population Analysis of LiH and HF

Following the analysis proposed by Mulliken, SCF LCAO-MO coefficients for LiH and HF are used to obtain qualitative information about the electron distributions in these molecules. Several additional aspects of population analysis are considered: the variation of atomic and overlap populations with internuclear distance and with choice of basis atomic orbitals, and the extent to which CI alters the qualitative description. It is shown that at equilibrium distances the results appear to be qualitatively unchanged by CI but are rather sensitive to the choice of basis functions.