Density functional theory studies of Ir2NiSn and Ru2NiSn Heusler alloys

Ir₂NiSn and Ru₂NiSn alloys were evaluated using density functional theory approach and the FM-L2₁-type structure was obtained as the stable exothermic ground state configuration for the Ir₂NiSn and Ru₂NiSn alloys. The stability of the compounds alloys under investigation is substantiated by formation energy calculations, which consistently indicate negative formation energies. The formations energies of Ir₂NiSn and Ru₂NiSn Heusler alloys are −3.66 eV and −5.95 eV respectively. The elastic properties demonstrate that the alloys are stable elastically, ductile and anisotropic. The calculated electronic density of state shows that the alloys have metallic character in both the spin-down and spin-up configurations. The spin configuration for the alloys is attributed to the 3d orbitals of Ni and Ir/Ru atoms. The significant d-d orbital hybridization obtained between the transition metal atoms of the Ni and Ir/Ru atoms resulted in the reduction of states at the spin-up level around the valence and conduction bands. Within the GGA-PBE (mBJ-GGA-PBE) approach, the total spin magnetic moments per unit cell of Ir₂NiSn and Ru₂NiSn alloys are 1.13 (1.43) and 1.84 (2.22) μ_B. The mechanical properties, including the bulk modulus, shear modulus, and Young's modulus, were calculated for both alloys, and stability was observed across both alloys. The evaluated Ir₂NiSn and Ru₂NiSn alloys have potential application as spintronic materials.