Electronic structure calculations and ground state properties of V 4N, FeV 3N and VFe 3N nitrides and ordered FeV 3 and VFe 3 compounds

Abstract

In this work, self-consistent band structure calculations were performed for the nitrides V 4N, FeV 3N and VFe 3N to investigate the influence on the electronic structure and ground state properties of V 4N due to the substitution of vanadium atoms by iron atoms. These calculations were done also for the ordered FeV 3 and VFe 3 compounds (in the FCC structure) to understand clearly the effects of inclusion of nitrogen in such alloys. The linear muffin-tin orbital (LMTO) method was employed and the calculations were performed at several lattice parameters in order to obtain the equilibrium volumes of these compounds. The present calculations show that while FeV 3 is nonmagnetic, VFe 3 exhibits a ferrimagnetic order with magnetic moments of −0.25μ B and 0.77μ B at vanadium and iron sites, respectively. Ferromagnetic calculations for V 4N, FeV 3N and VFe 3N give null magnetic moment, that is, the nonmagnetic state is the stable phase of these nitrides and the calculated lattice parameters are 7.52 a.u. for V 4N, 7.42 a.u. for FeV 3N and 7.04 a.u. for VFe 3N. The analysis of the density of states at equilibrium volume and the results for the charge transfer makes clear why these vanadium nitrides are nonmagnetic.