Effects of applied different potentials on electronic and Half-Metallic characteristics and investigated Pressure-Dependent elastic and thermodynamic properties of VRu2Br4 spinel

Abstract

The electronic and half-metallic characteristics and the pressure-dependent elastic and thermodynamic properties of VRu2Br4 spinel were calculated using different potentials. Firstly, the magnetic phases of VRu2Br4 spinel were investigated, and the FM phase was obtained as more stable than the AFM and NM phases. The lattice parameter and magnetic moment obtained at this stability are 10.93 Å and 10.00 µB/f.u, respectively. The most magnetic contribution came from V with 2.302 µB. Then the electronic calculations are performed by applying the GGA + mBJ and GGA + U (U = 1, 2, and 3 eV) potentials. While the energy gap is obtained as 0.210 eV in the GGA method, these are obtained as 1.282 eV, 0.693 eV, 1.200 eV, and 1.718 eV at GGA + mBJ, GGA + 1 eV, GGA + 2 eV, and GGA + 3 eV, respectively. The elastic calculation results show that VRu2Br4 spinel is stable. While the bulk, shear, and Young’s modulus values increase with the applied pressure, the B/G and Poisson’s ratios decrease. At 0 GPa pressure, the B/G and Poisson’s ratios were obtained as 2.48 and 0.322, respectively. Therefore, spinel shows ductile properties at 0 GPa pressure. These values were 1.75 and 0.26, respectively, at 10 GPa pressure. These results are boundary conditions for the brittleness and ductility properties of materials. Therefore, VRu2Br4 spinel starts to show a brittle character with increasing pressure. According to its thermodynamic properties, at 0 GPa pressure and 0 K temperature, Debye temperature is 257.22 K, while the Uvib, and Fvib energy values are 33.683 kJ/mol.