Quasiparticle energy bands of transition-metal oxides within a model GW scheme

Abstract

We calculate the quasiparticle band structure of NiO and ${\mathrm{CaCuO}}_{2}$ by using a model self-energy correction which approximates closely the GW method 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 demonstrate that the addition of self-energy corrections to local-spin-density 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 found in our calculations.