Frenkel pair formation energy for cubic Fe$_3$O$_4$ in DFT+U calculations

Abstract

Ab initio modelling of point defects in the cubic phase of magnetite faces two problems: the cubic structure becomes unstable below the Verwey temperature and there is no consensus on the electronic structure of the cubic phase (if there is a band gap, what type of symmetry of the wavefunction should be considered and how to describe strong electronic correlations). In this paper, we show that the comparison of the experimental data on the band gap and the Frenkel pair formation energy with the first-principles calculations allows to determine a consistent DFT+U model of cubic Fe$_3$O$_4$.