A combined DFT, DFT + U and mBJ investigation on electronic structure, magnetic, mechanical and thermodynamics of double perovskite Ba2ZnOsO6

•First theoretical prediction on electronic structure results of Ba2ZnOsO6.•Electronic structure presents the half-metallic nature for the compound.•Magnetic study presents the ferromagnetic nature.•Thermodynamic properties have been calculated within quasi-harmonic Debye model. First successful ab initio calculations on electronic structure, magnetic, elasto-mechanical and thermodynamic properties of cubic double perovskite oxide Ba2ZnOsO6 has been effectively calculated within density functional theory via full potential linearized augmented plane wave (FP-LAPW) method. The structural investigation exposes the ferromagnetic phase stability of the compound. The spin polarized electronic and magnetic properties were calculated within generalized gradient approximation (GGA), Hubbard approximation (GGA + U), mBJ (modified Becke-Johnson approximation). The electronic profile establishes half-metallic nature for the compound. The calculated total spin magnetic moment was found equal to 2 µB. The elastic constants have been calculated and used to predict mechanical stuffs like Shear modulus (G) Poisson ratio (ν) and anisotropic factor (A). The calculated B/G and Cauchy pressure (C12-C44) both characterize the material as brittle. The thermodynamic parameters like heat capacity and Debye temperature have also been predicted in the temperature range of 0 K–1000 K.