Electronic structure of MnO and CoO from the B3LYP hybrid density functional method

Abstract

The electronic and magnetic properties of CoO and MnO have been studied with the B3LYP hybrid density functional method. The ground states have been correctly predicted by the B3LYP functional, and it gives better results for energy gaps, magnetic moments, and core-level binding energies than the generalized gradient approximation (GGA) and the unrestricted Hartree-Fock (UHF) method. The B3LYP results for energy gaps, magnetic moments and core-level binding energies are between the GGA and UHF ones for antiferromagnetic, ferromagnetic and nonmagnetic phases of MnO and CoO. Although the two materials have same structure and antiferromagnetic ordering, the electronic structures near the Fermi energies are different. The magnetic coupling constants of CoO are much larger than the ones of MnO. The hyperfine coupling constants and electric field gradients are also calculated for further comparisons with experiment.