Structural, electronic, elastic and mechanical properties of novel ZrMnAs half Heusler alloy from first principles

Abstract

Abstract The influence of the properties of various materials researched on in literature such as the generalized Slater-Pauling behavior, half metallic property, and the effect of crystalline ordering, hydrostatic strain, thermodynamic properties, elastic behavior and more, have significant effects on the behavior of the materials hence rendering many half Heusler (HH) alloys ineffective for application in spintronics. We report the effect of Slater-Pauling behavior, half metallicity and crystalline ordering on the properties of three distinct phases of novel HH ZrMnAs (VEC\u202f=\u202f16) alloy which are α - [As (0, 0, 0), Mn (0.5, 0.5, 0.5), Zr (0.25, 0.25, 0.25)] phase, β - [Mn (0, 0, 0), Zr (0.5, 0.5, 0.5), As (0.25, 0.25, 0.25)] phase and γ - [As (0, 0, 0), Zr (0.5, 0.5, 0.5), Mn (0.25, 0.25, 0.25)] phase. With emphasis on effect of the interaction of magnetic-rich Mn at all possible Wyckoff positions. The most stable phase in the face of the three phases checked is the γ - phase and it exhibits a stable half metallic behavior under hydrostatic pressure at lattice parameters between 10.84 a.u. and 12.04 a.u. It also has a magnetic moment of 2 μB in line with the Slater-Pauling rule for half metallic materials with a half metallic band gap of 1.6\u202feV. The electronic structure calculation reveals a semiconducting band gap in the majority band and a metallic behavior in the minority band of the alloy. Confirming a half metallic character in the γ - phase of the alloy hence, presenting it as a promising material for application in spintronic devices. The elastic property investigation of the alloy shows that the β - and γ - phases has a bulk to shear modulus (B/G) ratio of 4.364 and 4.518 respectively as against the critical value of 1.75 confirming they are ductile materials.