Extended DFT+U+V method with on-site and inter-site electronic interactions

TL;DR

This paper introduces an extended DFT+U+V method that incorporates both on-site and inter-site electronic interactions, improving the modeling of systems with hybridized and partially localized electrons.

Contribution

It generalizes the DFT+U method by including inter-site interactions, enabling more accurate descriptions of diverse materials with hybridization effects.

Findings

Accurately models Mott insulators like NiO.

Effectively describes covalent insulators such as Si and GaAs.

Provides a unified approach for diverse electronic systems.

Abstract

In this article we introduce a generalization of the popular DFT+U method based on the extended Hubbard model that includes on-site and inter-site electronic interactions. The novel corrective Hamiltonian is designed to study systems for which electrons are not completely localized on atomic states (according to the general scheme of Mott localization) and hybridization between orbitals from different sites plays an important role. The application of the extended functional to archetypal Mott - charge-transfer (NiO) and covalently bonded insulators (Si and GaAs) demonstrates its accuracy and versatility and the possibility to obtain a unifying and equally accurate description for a broad range of very diverse systems.