Importance of the V 3d-O 2p hybridization in the Mott-Hubbard material V2O3

TL;DR

This study investigates the electronic structure changes in V2O3 across the Mott-Hubbard transition, emphasizing the role of V 3d-O 2p hybridization and multi-band effects using a cluster model.

Contribution

It introduces a comprehensive cluster model that includes both local and non-local fluctuations to explain the electronic structure evolution in V2O3.

Findings

Reproduces spectral changes in V 1s core-level spectra.

Identifies the roles of coherent and incoherent spectral features.

Highlights the necessity of a multi-band approach for Mott-Hubbard transition.

Abstract

We studied the changes in the electronic structure of V2O3 using a cluster model. The calculations included fluctuations from the coherent band in the metallic phase, and non-local Mott-Hubbard fluctuations in the insulating phase. The incoherent structure is mostly related to the usual ligand screening channel (3d2L). The coherent peak in the metallic phase corresponds to coherent band fluctuations (3d2C). The non-local screened state in the insulating phase (3d2D) appears at higher energies, opening the band gap. The photon energy dependence of the spectra is mostly due to the relative V 3d and O 2p cross sections. The present model reproduces also the observed changes in the V 1s core-level spectra. The above results suggest that the Mott-Hubbard transition in V2O3 requires a multi-band model.