AB INITIO STUDIES ON BEH+ (X1SIGMA+)

A 38-configuration wavefunction was calculated for BeH+ (X 1∑+) at R = 2.48 bohr, the experimental equilibrium R distance, to give an energy of -14.92196 hartree and an electric moment of 1.578 a.u. This function gave 79% of the binding energy and 73% of the correlation energy. Comparative studies were made with the important zeroth-order configurations, Be+(2S)H(2S), Be +(2P)H(2S), Be2+( 1S)H-(1S), and Be(1S)H+, and with previous work on the LiH (X1∑+) molecule. The polar nature of BeH+ appears to be best described in terms of a valence-bond picture, where (2s-2s-2pa) hybridization amply explains the charge transfer.