Osmium Containing Double Perovskite Ba₂XOsO₆ (X = Mg, Zn, Cd): Important Candidates for Half-Metallic Ferromagnetic and Spintronic Applications

Abstract

In this chapter, Osmium-based double perovskites Ba 2 XOsO 6 (X = Mg, Zn, Cd) have been investigated for their magnetic structure, electronic, elastic, mechanical and thermodynamic belongings. These materials have been recently reported experimentally for their magnetic structure. Here, we report the first successful ab initio calculations on the physical properties of these materials. The structural optimization for these Ba 2 XOsO 6 (X = Mg, Zn, Cd) double perovskite compounds has been finalized within density functional theory via full potential linearized augmented plane wave (FP-LAPW) method. The structural investigation exposes the ferromagnetic phase stability of these compounds. The spin-polarized electronic and magnetic properties were calculated within generalized gradient approximation (GGA), Hubbard approximation (GGA+U) and modified Becke-Johnson approximation (mBJ). The electronic profile establishes the half-metallic nature for all the three compounds. The total spin magnetic moment was found to be an integer value of 2 μ b. The elastic constants have been calculated and used to predict mechanical stuffs like Shear modulus (G), Poisson ratio (v) and anisotropic factor. The calculated B/G and Cauchy pressure (C 12-C 44) both characterize these materials as brittle. The thermodynamic parameters like heat capacity and Debye temperature have been predicted in the temperature range of 0-1000 K.