Theoretical study of structural, electronic and thermal properties of Zn1−xBexS ternary alloy

The structural, the electronic and the thermal properties of Zn1−xBexS ternary alloy have been calculated using the full-potential linearized-augmented plane wave (FP-LAPW) method. The exchange and correlation potential is treated by the generalized-gradient approximation (GGA) using the Perdew–Burke–Ernzerhof (PBE) parameterization. Moreover, the Engel–Vosko GGA formalism is also applied to optimize the corresponding potential for band structure calculations. The ground state properties such as lattice constants and bulk modulus are in good agreement with numerous experimental and theoretical data. The thermodynamic stability of this alloy was explained by calculating the phase diagram. The quasi harmonic Debye model, using a set of total energy versus volume calculations obtained with FP-LAPW method is applied to study the thermal and vibrational affects. Temperature effect on the lattice parameter, thermal expansion coefficient, heat capacity and Debye temperature is determined from the non-equilibrium Gibbs function.

► The lattice constant of Zn1−xBexS alloy exhibits a large deviation from Vegard’s law. ► This alloy is stable at high temperature. ► The quasi-harmonic Debye model was successfully applied to the variations of the thermal expansion coefficient, heat capacity and Debye temperature as a function of the temperature.