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arXiv · 1506.05778

An alloy calculation of pure antiferromagnetic NiO

Luiz G. Ferreira
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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.

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Luiz G. Ferreira. 2015-06-18. An alloy calculation of pure antiferromagnetic NiO. https://arxiv.org/abs/1506.05778

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