A Computational Study of Nickel Ferrite

Abstract

Magnetic properties and electronic structure of nickel ferrite are studied using hybrid density functional theory. In the calculation, the exchange correlation is a mixture of Fock exchange, local spin density approximation (LSDA) and generalized gradient approximation (GGA). The weighting factor ( w) of the Fock term and a scaling factor of the 3d orbitals of Fe 3+ ( α) are introduced as fitting parameters. All nearest neighbor exchange constants for inter and intra A and B sites of the spinel structure of nickel ferrite are calculated from the energies of different magnetic structures. Local magnetic moments of the ions on the A and B sites are calculated by the Mülliken population analysis. Moreover, the density of states is calculated to show the insulating nature of nickel ferrite. The band gap and intra-site Coulomb repulsion are extracted from the calculated density of states. The charge density map is calculated to visualize the electrons in nickel ferrite.