# Electronic Structure Properties of UO2 as a Mott Insulator

## TL;DR

This study employs advanced density functional theory methods to accurately characterize the insulating electronic structure of uranium dioxide, addressing limitations of standard approximations.

## Contribution

It demonstrates the effectiveness of LDA+U and HSE hybrid functionals in correctly predicting UO2 as a Mott insulator, improving upon traditional DFT approaches.

## Key findings

- UO2 is confirmed as a Mott insulator with a proper band gap.
- Standard DFT approximations incorrectly predict metallic behavior.
- Hybrid functionals and Hubbard corrections yield results consistent with experiments.

## Abstract

In this work using the density functional theory (DFT), we have studied the structural, electronic and magnetic properties of uranium dioxide with antiferromagnetic 1k-, 2k-, and 3k-order structures. Ordinary approximations in DFT, such as the local density approximation (LDA) or generalized gradient approximation (GGA), usually predict incorrect metallic behaviors for this strongly correlated electron system. Using Hubbard term correction for f-electrons, LDA+U method, as well as using the screened Heyd-Scuseria-Ernzerhof (HSE) hybrid functional for the exchange-correlation (XC), we have obtained the correct ground-state behavior as an insulator, with band gaps in good agreement with experiment.