First principles study on half-metallic properties of Heusler compounds Ti2VZ (Z=Al, Ga, and In)

Abstract

First principles calculations using the self-consistent full-potential linearized augmented plane wave (FPLAPW) method in the framework of density functional theory (DFT) were performed to study the electronic structures and magnetic properties of new full-Heusler compounds Ti2VZ (Z=Al, Ga, and In). Electronic structure calculations showed that Ti2VZ (Z=Al, Ga, and In) compounds in AlCu2Mn-type are conventional ferrimagnets. The Ti2VAl, Ti2VGa, and Ti2VIn compounds in the CuHg2Ti-type structure have half-metallic characteristics with a respective majority band gap of 0.52, 0.51, and 0.59eV at the equilibrium lattice parameter. The origin of half-metallicity in these compounds was also discussed. The total magnetic moments of Ti2VZ (Z=Al, Ga, and In) compounds in the CuHg2Ti-type structures were 2μB per formula unit which were in agreement with Slater–Pauling rule (Mtot=18−Ztot). The Ti2VAl, Ti2VGa, and Ti2VIn compounds in the CuHg2Ti-type structure respectively showed half-metallic characteristics at lattice constants ranges of 6.12–7.17Å, 5.99–7.12Å, and 6.31–7.06Å, indicating the lattice distortion did not affect the half-metallic properties of these compounds which makes them interesting materials in the spintronics field.