Insights into the physical properties of inverse-Heusler alloy Cr₂CoGa via density functional theory

Abstract

First-principles analyses are accomplished on the structural, mechanical, thermal, electronic, and optical properties of inverse-Heusler alloy Cr2CoGa using density functional theory. Our determined lattice parameters agree very well with prior findings. The mechanical properties of both cubic and tetragonal phases of Cr2CoGa compound are thoroughly investigated. The elastic constants meet the Born criteria for mechanical stability of the studied compound. The ductile behavior is exhibited by the calculated Pugh’s ratio 2.66 and 2.91 as well as the Poisson’s ratio 0.33 and 0.35 for cubic and tetragonal phase, respectively, and the tetragonal phase is more ductile comparing this two phases. The universal elastic anisotropy of cubic and tetragonal Cr2CoGa is 0.25 and 0.28, respectively, revealing their anisotropic nature, which is also confirmed by the non-spherical 3D anisotropy contour plots. The estimated Debye temperature and minimum thermal conductivity suggest potential application of Cr2CoGa as a thermal barrier coating. The calculated electronic band structure and density of states suggest the metallic characteristics of Cr2CoGa. Moreover, the important optical parameters, namely, dielectric constants, refractive index, absorption coefficient, photoconductivity, reflectivity, and loss function are also investigated and discussed towards the efficient applications of Cr2CoGa.