Optical property and electronic band structure of a piezoelectric compound Ga₃PO₇ studied by the first-principles calculation

The structure, electronic, and optical properties of a piezoelectric material, Ga₃PO₇, were studied by first-principles calculations in the framework of density functional theory. The calculated structure is in agreement with the experimental data. Band structure reveals that Ga₃PO₇ has a band gap of 3.69 eV. Analysis of partial density of states and Mulliken charge population indicates existence of GaO₅ and PO₄ anion groups in Ga₃PO₇. Furthermore, its optical properties, including dielectric constant, absorption, reflectivity, refractive index, and electron loss were calculated and analyzed, which show that Ga₃PO₇ has potential applications based on combination of its piezoelectric and optical properties.