First principle studies of structural, elastic, electronic and optical properties of Zn-chalcogenides under pressure

Abstract

Structural, elastic, electronic and optical properties of zinc-chalcogenides (viz. ZnX, X = S, Se and Te) are studied in zinc-blende structure under hydrostatic pressure using the full-potential linearized augmented plane wave method. Generalized gradient approximation is used for exchange correlation potentials. Pressure-dependent lattice constants and bulk moduli are obtained using the optimization method. Young's modulus, Poisson's ratio, internal strain parameter and anisotropy are also calculated. The higher values of Young's modulus in comparison to the bulk modulus show that these materials are hard to break. Poisson's ratio is computed for the first time for these materials to the best of our knowledge and its values show higher ionic contribution in these materials. Modified Becke and Johnson (mBJ) method is used to study band gaps, density of states, dielectric function and refractive index. Electronic study shows direct band gaps convert to indirect band gaps with increasing pressure in the case of ZnS and ZnTe. We compared our results with other theoretical and experimental results. Our results are far better than other theoretical results because mBJ is the best technique to treat II–VI semiconductors.

Metal mono-chalcogenides ZnX and CdX (X = S, Se and Te) monolayers: Chemical bond and optical interband transitions by first principles calculations

“…The energy band gaps of these structures in bulk phase were reported as direct band gaps 8,12 , and data have been reported here is in good agreement with these previous works (see supplementary data). The monolayer energy band structures of these compounds will be investigated below.…”

First-principles study of phase transition, elastic and thermodynamic properties of ZnSe at high pressure

“…The discrepancy between our computed results and the experimental values 36 for the elastic constants of B3 structure is acceptable. Meanwhile there is well in line between our obtained results and some previous theoretical results 32,33,37,38 for B3 phase. To the best of my knowledge, there are no experimental values of the elastic constants for B1 structure at elevated pressure.…”

“…In order to obtain the bulk modulus B and shear modulus G, the Hill model is applied, which takes the arithmetic average of the Voigt 40 and Reuss models 41 . For cubic system, Hill shear modulus G and bulk modulus B are taken in the form of 42 : 82.45 38 42.71 38 35.5 38 Exp. 81 36 48.8 36 www.nature.com/scientificreports www.nature.com/scientificreports/…”

Cobalt-substituted ZnS QDs: a diluted magnetic semiconductor and efficient photocatalyst

“…9–11 In addition to its photocatalytic activities, the ZnS quantum dots serve as an effective host for diluted magnetic semiconductors (DMSs), and by substituting appropriate magnetic ions, magnetic properties can be introduced within it to explore the spintronics domain. 12,13…”