Structural, electronic and optical properties of cubic fluoroelpasolite Cs2NaYF6 by density functional theory

Abstract

First-principles full-potential linearized augmented plane-wave method based on density functional theory is used to investigate the structural, electronic and optical properties of the cubic fluoroelpasolites Cs2NaYF6 within the local density approximation (LDA) and generalized gradient approximation (GGA) for potential exchange correlation. The modified Becke–Johnson (mBJ) potential approximation is also used for calculating the electronic and optical properties of the material. We have analyzed the structural parameters, total and partial densities of states, dielectric functions, absorption and reflectivity. The results show that the band structure of the fluoroelpasolites Cs2NaYF6 has an insulating behavior for the two directions of spin and as a result there is no net magnetic moment. A wide band gap of 9.6 eV is obtained with mBJ-GGA, which allows the application of this material as X-ray storage phosphor materials and scintillators.