A First-Principles Study of Structural, Electronic and Optical Properties of Be_0.75Zn_0.25S Semiconducting Alloy

Abstract

In this work, we report the theoretical study of structural, electronic, and optical properties of Be_0.75Zn_0.25S semiconducting ternary alloy using the first-principles density functional theory approach. The calculations are performed using the Plane Wave Self Consistent Field (PWSCF) method implemented in the QUANTUM ESPRESSO code. The two approaches are used to calculate the properties of semiconducting alloy: the first is local density approximation, and the other is generalized gradient approximation in the framework of the density functional theory. Among structural properties, the ground state equilibrium lattice constant, bulk modulus, elastic constants, shear modulus, and Poisson ratio are computed for Be_0.75Zn_0.25S semiconducting ternary alloy. The electronic band structure is calculated to characterize the electronic properties, and bandgaps and electronic charge transfer between the cation and anion are evaluated. The optical nature of alloy is characterized by computing the static dielectric constant and refractive index. The computed parameters are compared with the available theoretical calculations due to the absence of experimental work on this system.