STRUCTURAL, ELECTRONIC, AND OPTICAL PROPERTIES INVESTIGATION OF ZnSe CUBIC SPHALERITE COMPOUNDS USING DENSITY FUNCTIONAL THEORY (DFT)

Abstract

Theoretical investigation of the structural, elastic, electronic and optical properties of ZnSe using the plane-wave pseudo potential formalism method of density functional theory with local density approximation (LDA) and generalized gradient approximation (GGA) as exchange-correlation potentials (DFT). The optimal structure of the binary semiconductor ZnSe crystallized in the complex phase of sphalerite was determined by studying the energy as a function of the basic unit volume. The calculated equilibrium lattice constants, bulk moduli and volumes are in reasonable agreement with the available experimental results. The electronic and chemical bonding properties were investigated by calculating the band structure, density of states and Mulliken population. We found that for ZnSe, the band gap of LDA is 1.33 eV and that of GGA is 1.34 eV. In addition, optical properties (absorption coefficients) were calculated.