Theoretical Prediction of Structural, Magnetic and Electronic Properties of a New SiRbCa Heusler Alloy

Abstract

Density functional theory (DFT) within the full-potential linearized augmented plane waves (FP-LAPW) method have been employed to investigate the structural, electronic and magnetic properties of a new half-Heusler SiRbCa alloy in its three crystalline phases (α, β and γ) using two alternative approximations; GGA-PBE and mBJ-GGA-PBE that account for spin polarization. For the three phases α, β and γ of half-Heusler SiRbCa alloy, we have observed that the ferromagnetic phase is energetically beneficial relative to the magnetic phase, which is most stable for the three phases. Band structure and density of state calculations using GGA-PBE and mBJ-GGA-PBE are illustrated, the half-Heusler SiRbCa alloy behaves as a semiconductor for the majority of its spins and metal for the minority of its spins, giving a unique half-metallic nature. This approximation maintains the properties of having a direct fundamental gap of X → X.