First principle investigation of the electronic structure of spinel Fe3O4

A comparative study of the structural, electronic and magnetic properties of ferrimagnetic cubic spinel magnetite (Fe3O4) has been performed in the present report, using LDA, GGA with PBE functional and GGA+U approximations within the framework of density functional theory. Study reveals smaller relative deviations in the structural parameters from the experimental data with GGA compared to LDA. Total DOS and band structure results demonstrate half metallic behavior of Fe3O4. The value of the band gap calculated by GGA+U is found to be higher than that calculated by GGA and LDA which is in good agreement with the experimental value. The total magnetic moments of Fe3O4 are found to be nearly equal in all the approximations whereas the values of the partial magnetic moments of Fe and O are increased and decreased respectively in GGA +U.