Electronic band structure and linear optical properties of paraelectricKIO3

Abstract

The electronic energy band structure, partial (PDOS) and total densityof states (DOS), and linear optical properties of the paraelectricKIO3 single crystal are calculated using density functional theory (DFT) in its localdensity approximation (LDA). The calculated band structure for paraelectricKIO3 indicates that the crystal has a direct bandgap. Using LDA and generalized gradient approximation(GGA), structural optimization has been performed. The optical spectra of the paraelectricKIO3 in the photon energy range up to 30 eV are investigated under the scissor approximation. Thereal and imaginary parts of the frequency-dependent linear dielectric function, as well asrelated quantities such as energy-loss function, refractive index and effective number of valenceelectrons, are calculated. The calculated structural optimization and bandgap of the paraelectricKIO3 have been compared with experimental data and have been found to be in good agreementwith the experimental results.