Wurzite

Werner s coordination theory, 1, 6 Whewellite structure, 6, 849 Wickmanite structure, 6, 849 Wilkinson s catalyst, 6, 239 Wilson s disease, 5, 721 copper, 6,648 removal, 6,769 copper complexes, 2,959 copper metabolism, 6,766 radiopharmaceutical agents, 6,968 Wolfram s red salt, 5,427 Wurzite... 

The Transition to the Sphalerite Structure.—The oxide, sulfide and selenide of beryllium have neither the sodium chloride nor the cesium chloride structure, but instead the sphalerite or the wurzite structure. The Coulomb energy for the sphalerite arrangement is... 

Sodium chloride structure Sphalerite or wurzite structure... 

The prediction may be made that the still unstudied crystal magnesium telluride, with the radius ratio 0.29, has the sphalerite or wurzite structure rather than the sodium chloride structure. 

The radius ratios for sphalerite and wurzite type crystals with eighteen-shell cations do not conform to our criterion, so that some other influence must be operative. Without doubt this is deformation. Here again it is seen that the tetrahedral structure is particularly favorable to deformation, for the observed Zn++—O distance (1.93 A.) is 0.21 A. shorter than the theoretical one, while in cadmium oxide, with the sodium chloride structure, the difference is only 0.01 A. 

It is also shown that theoretically a binary compound should have the sphalerite or wurzite structure instead of the sodium chloride structure if the radius ratio is less than 0.33. The oxide, sulfide, selenide and telluride of beryllium conform to this requirement, and are to be considered as ionic crystals. It is found, however, that such tetrahedral crystals are particularly apt to show deformation, and it is suggested that this is a tendency of the anion to share an electron pair with each cation. 

There are other allotropic forms of carbon, including graphite, Wurzite carbon... 

ZnO with a polar hexagonal wurzite structure can be described as being due to the hexagonal close packing of the... 

The compound ZnGa2S4 has a crystal structure which is closely related to the blende type (14). There is no appreciable range of composition for this compound. Two extensive homogeneity regions are observed, at elevated temperatures, one of the wurzite type near ZnS and the other of the blende type near Ga2S3. 

The formula at Eq. (4-28) applies to the wurtzite structure if nearest neighbors form a regular tetrahedron (the ideal axial ratio). We see this by observing that the same answer would have been obtained in the zincblende structure with a field along a [111] direction, and that one can go from the zincblende to the wurzite structure with bond rotations all made around that [111] axis. 

From Fisher Properties Wurzite-type structure, confirmed by XRD, BET specific surface area 14 mVg, particle diameter 4 pm [318, 1221]. 

From Aldrich or from Fisher Properties Wurzite, purity... 

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