Band theory and Mott insulators: Hubbard U instead of Stoner I.

Anisimov V.I., Zaanen J., Andersen O.K.

The authors propose a form for the exchange-correlation potential in local-density band theory, appropriate for Mott insulators. The idea is to use the 'constrained-local-density-approximation' Hubbard parameter U as the quantity relating the single-particle potentials to the magnetic- (and orbital-) order parameters. Their energy functional is that of the local-density approximation plus the mean-field approximation to the remaining part of the U term. They argue that such a method should make sense, if one accepts the Hubbard model and the success of constrained-local-density-approximation parameter calculations. Using this ab initio scheme, they find that all late-3d-transition-metal monoxides, as well as the parent compounds of the high-Tc compounds, are large-gap magnetic insulators of the charge-transfer type. Further, the method predicts that LiNiO2 is a low-spin ferromagnet and NiS a local-moment p-type metal. The present version of the scheme fails for the early-3d-transition-metal monoxides and for the late 3d transition metals.

Physical Review B, 44 943-54, 1991.

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