Showing papers on "Wurtzite crystal structure published in 1974"
TL;DR: In this paper, a survey is given on lattice data and structure types of 40 compounds of the type Cu2II-II-IV-S4(Se4) with II = Mn, Fe, Co, Ni, Zn, Cd, Hg and IV = Si, Ge, Sn.
231 citations
TL;DR: Graphite-like boron nitride was shock-compressed up to 550 kbar as discussed by the authors, and the X-ray diffraction pattern of the recovered specimen identified the wurtzite structure whose hexagonal cell dimensions were a 0 = 2.553±0.003 A, c 0 = 4.228± 0.004 A.
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TL;DR: In this paper, the emission spectra of sulfur in two modifications (zinc-blende and wurtzite structures) of ZnS and CdS are obtained with a two-crystal spectrometer.
Abstract: The $K\ensuremath{\beta}$ emission spectra of sulfur in $\ensuremath{\alpha}\ensuremath{-}\mathrm{MnS}$, FeS, CoS, NiS, and CuS, and in two modifications (zinc-blende and wurtzite structures) of ZnS and CdS are obtained with a two-crystal spectrometer. The spectra of FeS, CoS, and NiS consist of a broad band and are alike. The spectra from the modifications of ZnS and CdS are similar to each other. The spectrum of CuS consists of two prominent peaks and it is discussed in relation to the sulfur $K\ensuremath{\beta}$ emission spectra from $\ensuremath{\alpha}\ensuremath{-}\mathrm{sulfur}$ and NiS. The $K\ensuremath{\beta}$ emission bands of ZnS and CdS are comparatively narrow, while those of the other metal sulfides are very wide. Results are evaluated by comparing the $K\ensuremath{\beta}$ emission spectra of these metal sulfides with the $\mathrm{sulfur}\ensuremath{-}K$ absorption spectra and with the energy-band structures.
56 citations
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TL;DR: In this paper, single crystals of GaN have been grown from the vapour phase by the reaction of Ga and NH3 at 1000-1150 °C and their morphology has been studied.
46 citations
26 citations
TL;DR: In this paper, the structure and morphology of CdTe films deposited in vacuum, on glass substrates, at oblique vapor incidence angles and at substrate temperatures up to 250 °C, have been studied by reflection-electron diffraction and scanningelectron microscopy, so as to help in the understanding of their unusually high photoelectromotive force.
Abstract: Structure and morphology of CdTe films deposited in vacuum, on glass substrates, at oblique vapor incidence angles and at substrate temperatures up to 250 °C, have been studied by reflection-electron diffraction and scanning-electron microscopy, so as to help in the understanding of their unusually high photo-electromotive force. Thinner films developed sphalerite type of face centred cubic (c) structure with a0=6.48 A. Thicker films showed additional wurtzite type of hexagonal close packed (h) phase with a0=4.57 A, c0=7.47 A, and a large hexagonal (H) phase, a0=4.57 A, c0=11,27 A, with a corresponding reduction in the proportion of the c phase. For oblique vapor incidence, 1 − d {111} orientation of c phase and 1− d {00.1} orientation of h phase, both being close packed layers showed normal or only slightly oblique growth, while 1 − d {331} orientation of c phase and 1 − d {10.3} orientations of hexagonal phases showed oblique growth towards the vapor direction but not aligned with it. Hillock growth of ...
26 citations
TL;DR: In this article, the elastic and piezoelectric properties of AgI in the wurtzite phase were studied and compared with those of other covalently bonded compounds near Phillip's critical ionicity.
Abstract: We have studied the elastic and piezoelectric properties of AgI in the wurtzite phase. Transformed elastic constants for the zinc-blende phase are obtained and are compared with those of other covalently bonded compounds near Phillip's critical ionicity ($f=0.785$). This confirms the earlier reported trend in the approach to zero of the $\frac{({C}_{11}\ensuremath{-}{C}_{12})}{2}$ elastic constant as the covalent to ionic phase transition is approached, indicating a lattice instability owing to a vanishing of the bending force constant. The room-temperature hydrostatic pressure dependence of the elastic constants exhibits a peculiar hysteretic behavior, possibly related to a sluggish conversion from wurtzite to zinc-blende structure. The temperature dependence of the elastic constants is also reported. The piezoelectric constants were determined.
TL;DR: In this article, a theory is discussed explaining the dependence of the formation of zincblende and wurtzite structure in A II B VI compounds on deviations from the stoichiometric composition.
TL;DR: The pyrrolidine ring is puckered at the B-carbon atom, which deviates about 0-52 A from the best plane formed by the four remaining atoms as discussed by the authors.
Abstract: The crystal structure of the title compound has been determined by X-ray diffraction analysis. It crystallizes in the orthorhombic system, space group P212121, Z=4, with unit-cell dimensions a= 12.114, b=8.153, c= 12.102 A. The structure has been solved by direct methods; refinement was carried out by full-matrix least-squares procedures including anisotropic thermal parameters. The molecule consists essentially of two planes: the carboxylic group and the remaining atoms with the exception of the methyl groups. The pyrrolidine ring is puckered at the B-carbon atom which deviates about 0-52 A from the best plane formed by the four remaining atoms. The molecules are held together in the crystal in pairs by one hydrogen bond, O(2)...O(3) 2.63 A. Bond lengths and valence angles are comparable with those of various related compounds.
TL;DR: In this paper, the third-order elastic constants of hexagonal and cubic structures are related using an extension of a transformation derived by Martin, and the transformation is used to calculate the zinc-blende second and thirdorder elastic constant of CdS from the experimental wurtzite elastic constants.
Abstract: The third‐order elastic constants of hexagonal and cubic structures are related using an extension of a transformation derived by Martin. The transformation is used to calculate the zinc‐blende second‐ and third‐order elastic constants of CdS from the experimental wurtzite elastic constants. Also, the transformation is shown to give good results for some face‐centered‐cubic hexagonal closed‐packed polymorphic metals. In particular, the second‐order elastic constants of cobalt and thallium in the hexagonal structure are compared with those calculated from cubic elastic constants extrapolated from alloy data, and second‐ and third‐order hexagonal elastic constants of Co‐32% Ni are compared with those calculated from cubic elastic constants.
TL;DR: In this paper, electron spin resonance and optical absorption measurements for Co 2+ in structurally pure single crystals of cubic, hexagonal, and 4H polytype ZnS were reported.
TL;DR: In this paper, the reflectance spectra of the A and B excitons in β-AgI were measured on different crystallographic planes and the n = 2 state of the B exciton and the longitudinal transverse mixed modes were identified.
TL;DR: In this paper, the authors presented a paper on growing the crystal used in this paper and thanks the University of Alberta for financial support, under grant MA-3406, to M.J.B.
Abstract: We thank Dr W. B. T. Cruse for growing the crystal used here, Miss K. Hayakawa for drawing some of the diagrams and Mr L. Goulden for the photography. This paper is abstracted from the Ph. D. thesis of G.J.B.W. who thanks the University of Alberta for financial support. The crystallographic computer programs of F. R. Ahmed et al., NRC Ottawa, have been invaluable in this work. Financial support, under grant MA-3406, to M.N.G.J. from the Medical Research Council of Canada is gratefully acknowledged.
TL;DR: In this article, the total valence electronic charge densities for two semiconductors with layer structure were calculated using wavefunctions from pseudopotential energy band structure calculations at a representative k point.
Abstract: The total valence electronic charge densities for two semiconductors with layer structure-SnS2 and SnSe2-are calculated using wavefunctions from pseudopotential energy band structure calculations at a representative k point. A comparison is made between the charge density distributions for these two compounds and those of ZnS in the wurtzite structure.
TL;DR: The formation of thin AlN films and some of their electrical properties have been investigated in this article, where the films were prepared by exposing the surface of evaporated aluminium films to a glow discharge in pure nitrogen gas.