First principles calculations of structural, electronic, mechanical and thermoelectric properties of cubic ATiO<inf>3</inf> (A= Be, Mg, Ca, Sr and Ba) perovskite oxide

First principle calculation was performed to investigate material properties such as structural, electronic, mechanical and thermoelectric of ATiO3 (Be, Mg, Ca, Sr or Ba) a perovskite based oxide within density functional theory. Calculations were performed using PBEsol exchange correlation functional within generalized gradient approximation (GGA). Structural and electronic properties were elaborated since their effect gives information about the thermoelectric performance. The underestimate of band gap from DFT calculation were corrected by using DFT with Modified Becke and Johnson (mBJ). It was observed that compound with small band gap have higher electrical conductivity and at the same time, high performance of thermoelectric power factors. BeTiO3 was found to possess very low power factor due to its low value of Seebeck coefficient and electrical conductivity. Highest thermoelectric power factor was obtained in BaTiO3 at 1200 K. Elastic constant were used to explain the mechanical properties such as anisotropic, brittle characteristics, stiffness and many others.