QUASI-PARTICLE ENERGY-BANDS OF TRANSITION-METAL OXIDES WITHIN A MODELGW SCHEME

We calculate the quasiparticle band structure of NiO and CaCuO2 by usi ng a model self-energy correction which approximates closely the GW me thod of Hedin. We obtain energy gaps and magnetic moments in agreement with experiment. For NiO, our results agree with integrated and angle -resolved photoemission experiments in the low binding energy region. The spectral distributions of O 2p and Ni 3d states are discussed, in relationship with the available experimental data. Our results demonst rate that the addition of self-energy corrections to local-spin-densit y band calculations provides a meaningful description of many aspects of the electronic states of transition-metal oxides. As expected, the satellite structures observed in photoemission experiments are not fou nd in our calculations.