Structural, electronic, and optical properties of cubic perovskites BiMO3 (M = Al, Ga & In) - A computational study

The Density Functional Theory (DFT) incorporating Full Potential Linearized Augmented Plane Wave (FP-LAPW) was used for the study of BiMO3 (M = Al, Ga, and In). The energy band structure, the density of states (DOS), and charge density calculation were used for their structural, electronic, and optical properties identification. With the optimized energy, the band gap was found to be 0.315 eV of the indirect type. The Bi-O has ionic bonding, and M (Al, Ga, and In)-O has a mixture of ionic and strong covalent bonds. The energy range of 0-30 eV was used to study the optical properties. The zero frequency reflectivity is 56.96 %, with its maximum (29.34 %) at 14.02 eV, maximum energy loss indicating plasma resonance is at 28.19 eV, and optical conductivity at 7767.27 ohm- 1 cm-1) at 13.41 eV where the maxima of absorption coefficient lie. An indirect band gap of 0.315 eV between the M -Gamma symmetry point was found. Thus the observations showed their efficiency as memories, capacitors, actuators, sensors, piezoelectric devices, solar cells, and other devices.