Structural and electronic properties ofNi2MnGa

Abstract

The equilibrium structure and electronic properties of a ferromagnetic shape memory alloy ${\mathrm{Ni}}_{2}\mathrm{Mn}\mathrm{Ga}$ have been studied for both the martensitic and austenitic phases by the full potential linearized augmented plane wave method. We report the stable martensitic phase at $c∕a=0.97$ and the lattice constants are in good agreement with the experimentally reported values. The Ni $3d$ ${e}_{g}$ related minority-spin peak in the density of states (DOS) near the Fermi level $({E}_{F})$ in the austenitic phase splits into Ni $3{d}_{{z}^{2}}$ and $3{d}_{{x}^{2}\ensuremath{-}{y}^{2}}$ states in the martensitic phase. The minority spin DOS at ${E}_{F}$ varies with $c∕a$, while the majority spin DOS at ${E}_{F}$ remains almost unchanged.