First-principles study of the electronic and magnetic properties of Fe2MnAl, Fe2MnSi and Fe2MnSi0.5Al0.5

In this work, first-principles calculations of the structural, electronic and magnetic properties of Heusler compounds Fe2MnAl, Fe2MnSi and alloy Fe2MnSi0.5Al0.5 are presented. We have applied the full-potential linearized augmented plane waves plus local orbitals (FP-L/APW+lo) method based on the density functional theory (DFT). For the exchange and correlation potential the generalized-gradient approximation (GGA) is used. It is shown that the calculated lattice constants and spin magnetic moments are in good agreement with the available theoretical and experimental data. The calculated atomic resolved densities of states of Fe2MnAl, Fe2MnSi indicate half-metallic behavior with vanishing electronic density of states for minority spin at the Fermi level, which yields perfect spin polarization while for Fe2MnSi0.5Al0.5 shows nearly half-metallic behavior with small spin-down electronic density of states at the Fermi level.