Electronic structure, magnetism and thermoelectric properties of double perovskite Sr2HoNbO6

First principles calculations on structural, electronic, magnetic and thermoelectric properties of newly synthesized perovskite Sr2HoNbO6 are carried out at the behest of much reliable density functional theory (DFT). The equilibrium lattice parameters at the cost of structural optimizations are observed to agree with the available experimental data. Three different methods for exchange correlations are utilized to investigate the electronic structure of this oxide. Spin polarized band structure calculations predict the semiconducting nature of this compound along with a large energy gap of 3.6 eV. Ferromagnetic interactions among the constituent atomic spin moments determine the total magnetic moment μ = 4.0 μB for this material with a maximum contribution from μHo = 3.95 μB. In addition, the temperature dependent thermoelectric properties based on the electronic results of Sr2HoNbO6 in temperature range from 50 to 1000 K are investigated. The total negative Seebeck coefficient signifies the p-type conduction or holes as charge carriers along the selected temperature range. The outcome of this study specifies the maximum value of dimensionless figure of merit zT ≈ 0.97 at room temperature.