We have performed an extended x-ray-absorption fine-structure (EXAFS) measurement of ${\mathrm{Cd}}_{1\mathrm{\ensuremath{-}}\mathrm{x}}$${\mathrm{Mn}}_{\mathrm{x}}$Te solid solutions for various concentrations x in the single-phase range 0\ensuremath{\le}x\ensuremath{\le}0.7. Data been collected on Mn K, Cd ${L}_{\mathrm{III}}$, and Te ${L}_{\mathrm{III}}$ edges. found well-defined different nearest-neighbor Cd-Te Mn-Te distances almost independent x. A model microscopic structure...

The nearest-neighbor distances around Te atoms in the random semiconducting alloy ${\mathrm{Cd}}_{1\ensuremath{-}x}{\mathrm{Mn}}_{x}\mathrm{Te}$ have been determined by extended x-ray-absorption fine-structure technique. distribution of anion-cation is bimodal. A model microscopic structure zinc-blende-type ${A}_{1\ensuremath{-}x}{B}_{x}C$ ternary alloys based on a cations has developed. describes bimodal terms distortion anion sublattice, using only lattice constant and bond-stretching...

The authors present a band calculation for antiferromagnetic MnTe. MnTe is found to be semiconductor with an indirect energy gap of 0.35 eV. density states and reflectivity spectra are presented compared experiment. As result comparison they conclude that optical properties can described in the framework theory.

Abstract It is shown that inclusion of spin–orbit interaction and omission the usual two‐center approximation in second neighbour Slater‐Koster tight‐binding method leads to an improved interpolation formula for energy bands II–VI semiconducting compounds such as CdTe. Due it possible obtain inverted band structure HgTe. Reflectivity spectra are computed fairly good agreement with experiment, up 5 eV. A detailed discussion critical points contributed E 1 , + Δ 2 maxima carried out. Moreover,...

The reflectivity spectra of Cd 1-x Mn x Te, Zn S and Se in the 0.7-8.1 eV energy range have been investigated compared with other known results for these mixed crystals. On basis obtained a model electronic structure compounds is proposed.

X-ray near-edge absorption structure for ZnTe, CdTe, and HgTe has been studied with the use of synchrotron radiation. The ${L}_{1}$, ${L}_{2}$, ${L}_{3}$ edges have analyzed Cd Te in as well ${L}_{1}$ ZnTe K edge Zn ZnTe. experimental results are compared spectra which calculated on basis conduction-band state densities obtained from self-consistent linear muffin-tin-orbital calculations. A comparison theoretical yields most cases a good quantitative agreement, particular all analyzed. Due...

Abstract Measurements of positions the E 1 and l Δ fundamental reflection maxima for Cd x Hg − ;Te samples within composition range from  0 to 0.2 were performed. The relations ( ) [E + ]J found in this range. previous results referring same substances which had been questioned by otherinvestigators fully confirmed. An analysis all known until recently is presented.

Abstract The width of the energy gap at A‐point Brillouin zone was measured in temperature range from 100 to 315 K for Cd x Hg 1‐ Te solid solutions. Measurements were carried out content 0 17%. thermal coefficients E l and + Δ transitions determined above mentioned composition. Some anomalies 1 ( T ) dependence have been found volume compositions x̄ = 0.125. A possible connection between these inversion band structure is discussed.

The authors present the first self-consistent band-structure calculations for SixGe1-x alloys made using virtual-crystal approximation. theory is based on local-density formalism and non-local pseudopotentials, constructed according to Kerker's prescription (1980). crossover in lowest conduction band edge from Ge-like symmetry (L point) Si like ( Delta line) found at x=0.12 reasonable agreement with experimental value x=0.15. alloy composition dependence of direct-transition energies...

A self-consistent semirelativistic linear muffin-tin orbital calculation of the band structure is used in conjunction with local-density approximation to derive density states and direct interband contribution joint for CdTe. The imaginary part dielectric function, epsilon 2b( omega ), calculated inclusion dipole transition matrix elements. comparison made other theoretical experimental results an interpretation sharp structures absorption spectrum ultraviolet (UV) range presented....

Self-consistent semi-relativistic linear muffin-tin orbital calculations of the band structures are used in conjunction with local-density-approximation to derive complex dielectric function, epsilon ( omega )= 1( )+i 2( ), and reflectivity spectrum R( ) up 20 eV for three most common II-VI semiconducting compounds ZnTe, CdTe HgTe. The authors have interpreted sharp above approximately 9 as transitions originating metal d levels. It is shown that a very significant contribution UV energy...

Double perovskite materials have recently attracted a lot of attention from the scientific community studying luminescent for white light-emitting diodes (WLEDs), displays, and luminescence thermometry. A series Pr3+-doped Ba2MgWO6 (BMW) powder samples were prepared by two different synthesis methods: coprecipitation (C–P) method conventional high-temperature solid-state reaction (S–S), as material to improve quality LED lighting, their structural spectroscopic properties are described in...

Methanol ice has been studied in the field of astrochemistry for many years. As a simple organic compound, CH3OH is extremely interesting study formation and evolution. There are three forms methanol – amorphous, α-crystalline, β-crystalline. Although there studies focused on comparison crystalline amorphous phases terms chemical properties, lack systematic phase transition. Factors such as pressure, temperature, rate have an influence process In this study, temperature vibrational...

The x-ray absorption near edge structure (XANES) for ${\mathrm{Cd}}_{1\ensuremath{-}x}{\mathrm{Mn}}_{x}\mathrm{Te}$ and MnTe in the hexagonal zinc-blende has been studied compared with results of a self-consistent linear muffin-tin orbital calculation. It shown that $p\ensuremath{-}d$ hybridization effects are strong enough to make XANES spectra at Te ${L}_{1}$ ${L}_{3}$ edges sensitive energy position unoccupied Mn $3d\ensuremath{\downarrow}$ states. We present unique method finding states...

Recently, an ab initio total-energy calculation for the ordered ternary phases of a III-V zinc-blende semiconductor was reported [G.P. Srivastava, J. L. Martins, and A. Zunger, Phys. Rev. B 31, 2561 (1985)]. We compare these results with those simple empirical model. Both models are used in new approach to thermodynamic properties alloys including cation distribution mixed sublattice. The applicability is critically discussed.