First-principles study of structural, elastic, electronic, and optical properties of orthorhombic BiGaO3

The structural parameters, elastic, electronic, and optical properties of orthorhombic BiGaO3 were investigated by the density functional theory. The calculated structural parameters are in agreement with previous calculation and experimental data. The structural stability of BiGaO3 has been confirmed by calculations of the elastic constants. The energy band structure, density of states, and Mulliken charge population were obtained. BiGaO3 presents a direct band gap of 2.03 eV. Furthermore, the absorption spectrum, refractive index, extinction coefficient, reflectivity, energy-loss spectrum, and dielectric function were calculated. The origin of the spectral peaks was interpreted based on the electronic structures.