Non-Hartree-Fock mean fields for molecules: critical tests

Abstract
The ground-state energies of the three small molecules H2O, BH and FH are calculated by two different mean-field methods. A comparison of the results shows that the g-Hartree approach, recently introduced and amply applied to atoms, substantially overestimates the magnitude of the correlation energies. The results are discussed in the context of a general Fock operator with effective electronic charges.