LAUSR

Abstract Effects of doping of mercury atom(s) on optoelectronic properties of diatomic zinc chalcogenides are investigated theoretically by designing zinc-mercury-chalcogenide ternary alloys in zinc-blende (B3) phase at some specific Hg-concentrations and studying their optoelectronic properties using DFT based FP-LAPW approach. The WC-GGA functional is used in computing structural properties, while the spin-orbit coupling included electronic and optical properties are calculated using TB-mBJ, EV-GGA, B3LYP and WC-GGA functionals. In addition, electronic properties of mercury chalcogenides are calculated precisely using the GGA + U functional. The concentration dependence of lattice parameter and bulk modulus of each of the HgxZn1−xS, HgxZn1−xSe, HgxZn1−xTe alloy systems show nonlinearity. For each of the alloy systems, band gap decreases nonlinearly with increase in Hg-concentration in the unit cell and contribution from charge exchange to the band gap bowing is larger than that from each of the volume deformation and structural relaxation. The atomic and orbital origin of electronic states in the band structure of each compound is explored from its DOS. Covalent bonding between different constituent atoms in each compound is observed. Optical properties of each specimen are computed from the spectra of dielectric function, refractive index, extinction coefficient, normal incidence reflectivity, optical conductivity, optical absorption coefficient and energy loss function. Several calculated results have been compared with available experimental and other theoretical data.