Eur. Phys. J. B (2013) 86: 78
https://doi.org/10.1140/epjb/e2012-30929-8

Regular Article

Antiferromagnetic half-metallicity of transition metal nitrides under volume expansion

Department of Physics, College of Sciences, Shiraz University, 71454 Shiraz, Iran

^a e-mail: davatolhagh@susc.ac.ir

Received: 11 October 2012
Received in final form: 12 December 2012
Published online: 4 March 2013

Abstract

The transition metal pnictides ABX₂ have been recently proposed as half-metallic fully compensated ferrimagnets, also briefly referred to as half-metallic “antiferromagnets” [N. Long, M.Ogura, H. Akai, J. Phys.: Condens. Matter 21, 064241 (2009)]. In this work we carry out a systematic study of the more promising cases of the transition metal nitrides MnCoN₂ and NiCrN₂ on the basis of density functional theory in the framework of full-potential linearized augmented plane wave method. The electronic structures and the magnetic properties of the above hypothetical compounds in Zinc-blende-type, NaCl-type, and Wurtzite-type structure are calculated within generalized gradient approximation. The results reveal that, although these compounds are metallic in their bulk equilibrium in all three structures, they exhibit antiferromagnetic half-metallicity under negative stress or volume expansion in a limited range of lattice parameters, which is significantly larger than the equilibrium values. This suggests that a situation in which half-metallicity may arise, is when these compounds are coated on semiconducting layers of larger lattice constant.