AB-INITIO HARTREE-FOCK CALCULATIONS OF CAO, VO, MNO AND NIO

Ab initio Hartree-Fock calculations are reported of the electronic str uctures of CaO, VO, MnO and NiO. They are found to be essentially ioni c in nature with ground states that are insulating, and, in the case o f VO, MnO and NiO, high-spin antiferromagnetic. Calculated lattice par ameters, binding energies and bulk moduli compare in accuracy with tho se for closed-shell oxides such as Li2O, MgO and Al2O3. Differences ar e found in the upper part of the valence band between VO and MnO and N iO. In VO it is predominantly V(3d) in character, whereas in both MnO and NiO it is O(2p). In the case of NiO this seems to be in accord wit h oxygen K-edge data for LixNi1-xO.