Theoretical study of optoelectronic, elastic and mechanical properties of gallium modified barium titanate (Ba1-xGaxTiO3) perovskite ceramics by DFT

In this report, we study the gallium modified Barium titanate (Ga-BTO) Ba1-xGaxTiO3 with (x = 50 %) perovskite ceramics, which have not been synthesized experimentally to date. The density functional theory-based full potential linear augmented plane wave has been employed to determine the optoelectronic, elastic, and mechanical properties of pure and modified BaTiO3. Completely relaxed 2 x 2 x 2 of primitive five atoms' cells has been used for calculations. A large cut-off energy of 120 Ry has been used to eliminate the basics of plane wave-indicating wave functions. The influence of substitution of Ga on electronic structure and optical parameters such as reflectivity, refractivity, dielectric function, optical conductivity, extinction, and absorption coefficients are analyzed and elucidated with TDOS and PDOS. The Ga modified BTO manifests a forbidden energy gap of 1.84 eV. The static dielectric constant epsilon(1)(o) has values of 8.8 and 100 for pure and modified compounds respectively. Ga dopant improved the polarizing power of BTO and for the doped BTO imaginary part, epsilon(2)(omega)showed a prominent peak located at 3.9 eV. The optical properties show that perovskite compound substituted with Ga is a good absorber in the ultraviolet region and the modified material has a small value of reflectivity and static refractive index 12.2. The general profiles of optical spectra of modified BaTiO3 display highly desirable features like the prominent peaks of optical conductivity obtained at 4.2 and 5.8 eV for modified BTO that make it a promising candidate for optoelectronic and spintronics. Ga-modified BTO has higher ductility, modulus (169.96 GPa), and anisotropy (2.949) than pure BTO found by analyzing their elastic and mechanical properties.