First principle study of cubic perovskites: AgTF3 (T=Mg, Zn)

The structural, electronic and optical properties of AgTF3 (T=Mg, Zn) are calculated for the first time using the full-potential linearized augmented plane wave method within the generalized gradient approximation. Structural parameters of the compounds are found to be in reasonable agreement with the available literature. Both compounds are found to have narrow and indirect band-gaps. The calculated band gap for AgMgF3 is 0.78 eV and 0.75 eV for AgZnF3. It is observed that Ag-4d, Zn-3d and Ag-5s states controls the electronic properties of AgMgF3 and AgZnF3. The nature of chemical bonding in these compounds is discussed by the electron density plots. The results of complex dielectric constant, refractive index, normal-incidence reflectivity and optical conductivity are also presented in the incident photon energy range of 0-35 eV. The wide absorption energy range makes these materials suitable for different devices applications. (C) 2011 Elsevier B.V. All rights reserved.