Half-Metallicity in Ni2XMn Heusler Alloys (X?=?Fe, Co, Cr): Ab Initio Calculations

Ab initio calculations have been conducted on all-d light transition metals featuring full and inverse Heusler structures with the composition Ni2XMn, where X = Fe, Co, Cr. The analysis encompasses lattice parameters, bulk modulus, and formation energy, which are thoroughly examined across various magnetic orders. Additionally, the equilibrium structures are comprehensively characterized. Elastic constants are calculated and mechanical stability is thoroughly discussed. Furthermore, tetragonal distortions, following the Bain path, are computed, and a novel stable structure is introduced. Spin-resolved density of electronic states and band structures are scrutinized in detail. The findings reveal a behavior consistent with half-metallicity, even though the gaps between the conduction and valence bands are exceedingly small.