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Implementation of the Projector Augmented Wave LDA+U Method: Application to the Electronic Structure of NiO

O. Bengone·M. Alouani·P. Bloechl·J. Hugel
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Abstract

The so-called local density approximation plus the multi-orbital mean-field Hubbard model (LDA+U) has been implemented within the all-electron projector augmented-wave method (PAW), and then used to compute the insulating antiferromagnetic ground state of NiO and its optical properties. The electronic and optical properties have been investigated as a function of the Coulomb repulsion parameter U. We find that the value obtained from constrained LDA (U=8 eV) is not the best possible choice, whereas an intermediate value (U=5 eV) reproduces the experimental magnetic moment and optical properties satisfactorily. At intermediate U, the nature of the band gap is a mixture of charge transfer and Mott-Hubbard type, and becomes almost purely of the charge-transfer type at higher values of U. This is due to the enhancement of the oxygen 2p states near the top of the valence states with increasing U value.

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O. Bengone, M. Alouani, P. Bloechl, J. Hugel. 2000-03-10. Implementation of the Projector Augmented Wave LDA+U Method: Application to the Electronic Structure of NiO. https://doi.org/10.1103/physrevb.62.16392

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