Ab initio study of structural, electronic, and optical properties of the anti-perovskite compound Na3OCN

Abstract

This paper investigates the structural, electronic, and optical properties of the anti-perovskite compound Na3OCN for the first time. Calculations are performed using the first-principles density functional theory (DFT) within the generalized gradient approximation (GGA). The lattice parameters obtained from the optimal calculations are in relatively good agreement with the experimental data. The calculated electronic band structure and density of states (DOS) show a direct band gap of 2.76 eV which implies the semiconductor characteristics of this compound, an n-type semiconductor. The band gap decreases by applying the tensile or compressive strains to the compound. Moreover, the complex dielectric function of this compound is calculated. Then it is employed to obtain the other optical properties, such as absorption, reflectivity, refractive index, extinction coefficient, loss function, and optical conductivity, as a function of energy in the range of 0-35 eV. The results indicate that the applied strain can alter the optical band gap, absorption edge, and static values of the real part.