Comparisons of the Magnetic and Half-Metallic Properties of Sb-V-Te Compounds in Low and Rich Vanadium Region

The electronic, magnetic, and half-metallic properties of SbxV1-xTe (x = 0.0625, 0.125, 0.25, 0.75, 0.875, and 0.9375) compounds were investigated by first-principles method using WIEN2k computational program. First, SbTe compound obtained a non-magnetic character. Second, the structural properties of compounds were formed by V-addition. The ferromagnetic phases were obtained as the most energetically stable phases in each ratio. Then according to electronic calculations, compounds formed at the V-low region showed metallic character, while band gaps were observed in minority electrons in the V-rich region. In GGA method, the indirect band gaps around the Fermi energy level were calculated as 1.304 eV for Sb0.0625V0.9375Te, 1.008 eV for Sb0.125V0.875Te, and 1.063 eV for Sb0.25V0.75Te compounds. The band gaps were also investigated by using GGA + U method for U = 1, 2, 3, 4, and 5 eV. As the U values increased, the band gaps decreased in Sb0.25V0.75Te and Sb0.125V0.875Te compounds. Although the U values affect the band gaps compared to the GGA, there was no change in the magnetic properties. The total magnetic moments of cells were obtained as 46.0 mu(B)/cell for Sb0.0625V0.9375Te, 22.0 mu(B)/cell for Sb0.125V0.875Te, and 10.0 mu(B)/cell for Sb0.25V0.75Te compounds, respectively. Finally, the elastic stability conditions were provided by the V-rich Sb-V-Te compounds.