Theoretical investigation of the electronic and optical properties of Zn2OX (X = S, Se, Te) in chalcopyrite phase by full potential methods

A full potential linear muffin tin orbital (FP-LMTO) and linear augmented plane wave plus local orbital (APW + lo) approach is used to investigate the electronic and optical properties of Zn2OX (X = S, Se, Te) in the chalcopyrite phase. It is found that these compounds are direct band semiconductors and the value of band gap increases as one move from Te to S. The optical properties of these compounds namely the reflectivity, refractive index, extinction coefficient, absorption coefficient, real part of optical conductivity and electron energy loss are calculated and their spectra are analyzed. In addition, the band structure, density of states and the bowing parameter of the Zn2OX (X = S, Se, Te) semiconductors are also obtained and given. The trends in physical properties are also discussed and compared with the available results.