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• The frequencies of these phonons, and hence the dielectric constants, are found to be composition dependent. • The higher the dielectric constant is, the better a material functions as an insulator. • The compositional dependence of the features of interest display at all events non-monotonic behavior. • The survey may be beneficial for the distinguishing permission of CdZnS-stabilized quantum well apparatus. First-principles pseudo-potential computations established on the density functional perturbation theory have been utilized for calculating frequencies of optical phonons, high-frequency and static dielectric constants, Frӧhlich coupling parameter, Debye temperature of longitudinal phonon frequency and effective polar field for zinc-blende Cd x Zn 1-x S semiconductor ternary alloys. The frequencies of these phonons, and hence the dielectric constants, are found to be composition dependent. The higher the dielectric constant is, the better a material functions as an insulator. The large dielectric constant in Cd x Zn 1-x S is mainly due to a pseudo-potential of low frequency phonons with large mode effective charge. The predisposition of experimental consequences display shapely convention with our datum. Otherwise, our consequences are predictions. The compositional dependence of the features of interest display at all events non-monotonic behavior. The survey may be beneficial for the distinguishing permission of CdZnS-stabilized quantum well apparatus. [ABSTRACT FROM AUTHOR]

First-principles all electrons density-functional calculations for the band structure and magnetization of Zn1−xCoxO ternary magnetic alloys, in three phases namely zinc-blende, rocksalt and wurtzite have been reported. The computations are spin-polarized. An inspection of our electronic properties showed that the alloy system of interest exhibits a semiconducting character where the nature of the gap depends on the considered phase. An analysis of electronic charge density suggests that the bonding has a partially covalent character for ZnO which becomes weaker as far as the Co concentration increases. CoO is found to reach a total magnetization of 3 μB per cell for zinc-blende and rocksalt phases and 6 μB per cell for wurtzite phase. [ABSTRACT FROM AUTHOR]

A pseudopotential calculation of the electronic structure of AlGaSb ternary alloys in the zinc-blende structure has been performed. The compositional dependence of energy gaps, electron and heavy hole effective masses and ionicity of the material system of interest have been examined and discussed. Special attention has been given to the effect of the alloy disorder on the direct (-) bandgap energy. It is found that all features of interest vary monotonically with increasing the Al concentration . Besides, bandgap bowing parameters and extent of the direct-to-indirect bandgap transition have been determined. Our findings agree generally well with the data reported in the literature. Trends in ionicity are found to be consistent with the Phillips ionicity scale. [ABSTRACT FROM AUTHOR]

A pseudopotential scheme, which incorporates compositional disorder as an effective potential, is used so as to calculate the optical properties of Ga x In 1− x P ternary alloys in the zinc-blende structure. Generally, the agreement between our results and the existing data in the literature is reasonable. The composition dependence of the studied features showed a non-monotonic behaviour for most studied features. Reasons for these findings are discussed. Moreover, the effect of the compositional disorder on the features of interest has been examined and found to be important for the calculation of optical properties of Ga x In 1− x P. [ABSTRACT FROM AUTHOR]

We present spin-polarized density-functional theory calculations of the structural properties and optical spectra of Zn 1-x Co x O ternary alloys in the hypothetical zinc-blende, rocksalt and wurtzite structures. Our results are very accordant with those existing in the literature. Most of our findings are reported for the first time. Generally, the rocksalt structure is found to have the highest stiffness as compared to those of zinc-blende and wurtzite structures. The lattice parameters of alloys of interest vary in a non-linear way and hence do not obey to the Vegard's law. Analysis of the optical spectra shows that all optical features of interest are affected by both alloying and variation of structure giving thus novel optical properties. Moreover, it shows a good optical absorption in a wide photon energy range which seems to be more important for the rocksalt structure. The static refractive index values are reported for the different structures and for various compositions x. [ABSTRACT FROM AUTHOR]