Density-functional theory and NiO photoemission spectra

The generalization of the local-density-approximation method for the systems with strong Coulomb correlations is proposed, which restores the discontinuity in the one-electron potential as in the exact density functional. The method is based on the model-Hamiltonian approach and allows us to take into account the nonsphericity of the Coulomb and exchange interactions. The calculation scheme could be regarded as a first-principle method due to the absence of adjustable parameters. The method was applied to the calculation of the photoemission (x-ray photoemission spectroscopy) and bremsstrahlung isochromat spectra of NiO.