Coulomb interaction in oxygen \textit{p}-shell in LDA+U method and its influence on calculated spectral and magnetic properties of transition metal oxides

TL;DR

This paper explores the impact of including Coulomb interactions in oxygen p-orbitals within the LDA+U method, demonstrating improved accuracy in spectral and magnetic property predictions for transition metal oxides.

Contribution

It introduces the consideration of oxygen p-shell Coulomb interactions in LDA+U calculations, enhancing the modeling of strongly correlated oxides.

Findings

Improved agreement with experimental spectral data.

More accurate magnetic moment predictions.

Enhanced modeling of exchange interactions.

Abstract

Coulomb interaction between electrons on p-orbitals of oxygen atom in strongly correlated compounds is not negligible, since its value (U_p) has comparable order of magnitude with the value of Coulomb interaction on d-orbitals of transition metal atom (U_d). We investigate the effect of taking into account Coulomb correlations in oxygen p-shell in addition to the correlations in the transition metal d-shell in frame of the LDA+U method. Our calculations for NiO, MnO and La2CuO4 show that this additional correction in general improves the agreement with experimental data for the spectral (energy gap values, relative position of the main peaks in X-ray photoemission spectroscopy (XPS) and Bremsstrahlung isohromate spectroscopy (BIS)) and magnetic properties (magnetic moment values and intersite exchange interaction parameters values).