An alloy calculation of pure antiferromagnetic NiO

Abstract

We use the many techniques of alloy theory to study antiferromagnetic NiO, considered as an alloy of spin-up and spin-down Ni atoms. The questions are: the true antiferromagnetic ground state and the possibility of obtaining ferrimagnetic configurations. Further we use the GGA/LDA- 1/2 technique to investigate the electronic excitation spectrum. We found two valence bands and band gaps, of 4.0eV consistent with bremsstrahlung-isochromat-spectroscopy (BIS) result, and 1.2eV consistent with the known 10Dq value for the Ni++ ion. The features of a Mott insulator are presented without recurring to an electron-pair correlation.