Glasse chalcogenide

Silicate Glasses Deconvolution of Si NMR Spectra Connectivities in Glass Chalcogenide Glasses Gels... 

Other commercial glass systems include fluoride-based glasses chalcogenide and chal-cohalide glasses the amorphous semiconductors, silicon and germanium and glassy metals. 

Selenium chalcogenide glasses exhibit good infrared transmission properties. These are used as lenses (ZnSe, CdSe) in laser apphcations and have potential applications in fiber optics (qv) and in data storage and retrieval. 

The cadmium chalcogenide semiconductors (qv) have found numerous appHcations ranging from rectifiers to photoconductive detectors in smoke alarms. Many Cd compounds, eg, sulfide, tungstate, selenide, teUuride, and oxide, are used as phosphors in luminescent screens and scintiUation counters. Glass colored with cadmium sulfoselenides is used as a color filter in spectroscopy and has recently attracted attention as a third-order, nonlinear optical switching material (see Nonlinear optical materials). DiaLkylcadmium compounds are polymerization catalysts for production of poly(vinyl chloride) (PVC), poly(vinyl acetate) (PVA), and poly(methyl methacrylate) (PMMA). Mixed with TiCl, they catalyze the polymerization of ethylene and propylene. 

Chalcogenides of Cd are similar to those of Zn and display the same duality in their structures. The sulfide and selenide are more stable in the hexagonal form whereas the telluride is more stable in the cubic form. CdS is the most important compound of cadmium and, by addition of CdSe, ZnS, HgS, etc., it yields thermally stable pigments of brilliant colours from pale yellow to deep red, while colloidal dispersions are used to colour transparent glasses. 

The main problem in developing fibers for IR transmission is that silica glass is not transparent in that area of the spectrum. Suitable materials include the selenides and other chalcogenide glasses (particularly for the CO2 laser light source) and the fluorohafnate glasses. In addition, materials, such as zirconium fluo-... 

Se-I 100, 185). These chalcogenide halide glasses belong to the so-called "semiconducting glasses that have attracted much attention in solid-state physics, because of their physical properties (see Section XII,B) they are, however, not treated in this review. 

The unique features of chalcogenide glasses (Chap. 6), such as quasi-stability, photoconductivity, infrared transparency, non-linear optical properties, and ionic... 

Tanaka K (2001) Chalcogenide Glasses. In Encyclopedia of Materials Science and Technology, Elsevier Science Ltd Oxford ISBN 0-08-0431526, pp. 1123-1131 Ovshinsky SR (1968) Reversible Electrical Switching Phenomena in Disordered Stmctures. Phys Rev Lett 21 1450-1453... 

Interesting systems, mainly with respect to solid-state optoelectronics and chalco-genide glass sensors (due to ionic conductivity effects) are found among the Group IIIB (13) and IVB (14) chalcogenides, such as the p-type semiconductors MSe (M = Ga, In, Sn), SnS, and GeX (X = S, Se, Te). Some of the IIIB compounds. 

Compared to the corresponding polycrystalline metal chalcogenides, chalcogenide glasses exhibit better chemical stability in acidic and redox media and often... 

---