Poly selenides

In order to prepare transition-metal selenido clusters, different synthetic routes are presently available, such as those involving, as starting materials, diphenyl dis-elenide, phenylselenyl chloride,selenofene, trialkylsilyl selenides, " poly-selenide anions, " and phosphine selenides.Furthermore, small selenido clusters, such as [Fe2(//-Se2)(CO)6] and [Fe3(/i3-Se)2(CO)9], can be conveniently used to prepare larger mono- and bimetallic species, as described in Sec. 1.11.5. 

The same procedure is used for 063864 and Prg8e4. However, Nd yields only Ndi eg.s. The other rare earths do not form poly-selenides. The sesquiselenides of these elements are best prepared by treating the rare earth chlorides with Hg8e ... 

See the general references in the Introduction, and some more-specialized books [1-25]. Some articles in journals discuss synthetic catalysts for the photooxidation of water to oxygen [26] kinetics and mechanisms of metal-02 complexes [27] d-block-catalyzed oxidation of sulfur(IV), especially in the atmosphere [28] various metal-02 complexes [29] mainly mono- and poly-selenide and telluride complexes with d-block elements [30] heterogeneous redox catalysts for oxygen release [31] the kinetics and equilibria of oxygen species and metal ions [32] thio- and seleno-complexes of V, Mb, Ta, Mo, W and Re [33] and homonu-clear sulfur species, not emphasizing aqueous reactions [34]. 

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. 

Caesium selenide, 4265 Calcium poly sulfide, 3942 Calcium sulfide, 3941 Cerium trisulfide, 3967 Chromium(II) sulfide, 4245 Cobalt(II) sulfide, 4218 Copper iron(II) sulfide, 4269 Copper(II) sulfide, 4285 Europium(II) sulfide, 4293... 

Nickel AML, Seker E, Ziemer BP, Ellis AB. Imprinted poly (acrylic acid) films on cadmium selenide. A composite sensor structure that couples selective amine binding with semiconductor substrate photoluminescence. Chem Mater 2001 13 1391-1397. 

Colloidal sulfide, selenide, telluride, phosphide, and arsenide semiconductor particles are prepared by the controlled precipitation of appropriate aqueous metal ions by H2S, H2Se, H2Te, PH3, and AsH3, respectively. Colloids are stabilized, typically, by sodium poly-phosphate. A large number of experimental parameters determine the size, size distribution, morphology, and chemical composition of a semiconductor particles in a given preparation. Concentrations, rates, and the order of addition of the reagents the counterions selected ... 

Poly(p-phenylene oxide) is also a processible polymer, but its treatment with AsF5 leads only to rather poor conductivity77). The synthesis of poly(p-phenylene selenide) has been described by Jen et al. 78) and by Sandman et al. 79) but the polymer does not conduct even on prolonged exposure to AsF5. 

Pentacarbonyl(trimethylsilyl)manganese. VINYL FLUORIDES Pyridinium poly(hydrogen fluorideV-N-Bromosuccinimide. VINYLPHOSPHINES 2,4,6-Trii sopropy I benzenesulfonylhy drazine. VINYL SELENIDES Benzeneselenenyl halide-Silver nitrite. Diphosphorus tetraiodide. 

The first poly chalcogenide complex, K4USeg, was obtained by a solid-state reaction. It has a molecular sfructure with a distorted dodecahedral anion, [U(Se2)4] , which is isosfructural with the known peroxoanions [M(02)4]" , where M = V, Nb, Ta, Cr (n = 3) or Mo, W (n = 2). Recently, two additional uranium selenides have been synthesized, MU2Se6 (M = K+, Cs+), using a reactive flux method. The oxidation state of the uranium in these compounds was found to be tetravalent. The selenium has two distinct oxidation states, Se and one similar to a polyselenide network. 

Poly-p-phenylene Selenide and Poly-p-phenylene Telluride... 

Poly(phenylsilane)s have been used as radical-based reducing agents for organic halides [70]. The reduction of a bromide is given as an example in Eq. (32). 1,1,2,2-Tetraphenyldisilane has also been introduced as a diversified radical reagent for the reduction of alkyl bromides and phenyl chalcogenides [71]. An example with 3-cholestanyl phenyl selenide is given in Eq. (33). 

Nickel, A.M.L. Seker, F. Ziemer, B.P. Ellis, A.B. Imprinted poly (acrylic acid) films on cadmium selenide. A composite sensor structure that couples selective amine binding with semiconductor substrate photoluminescence. Chem. Mater. 2001, 13, 1391-1397. Sallacan, N. Zayats, M. Bourenko, T. Kharitonov, A.B. Willner, I. Imprinting of nucleotide and monosaccharide recognition sites in acrylamidephenylboronic acid-acrylamide copolymer membranes associated with electronic transducers. Anal. Chem. 2002, 74, 702 712. 

Variety of semiconducting material such as single and poly crystal silicon, amorphous silicon, Cadmium-Telluride (CdTe), Copper Indium/Gal-lium Di Selenide (CIGS) have been employed to form inorganic solar cell based on layers configuration to enhance absorption efficiency, conversion efficiency, production and maintenance cost. 

Recently, the spectroscopic identification of carbonyl teUuride, obtained by photolysis of H2Te in CO or 1 % CO/Ar matrices at 10 K, was reported. Carbonyl selenide is readily synthesized in situ from R2NC(0)Se R2NH2+ and acids, but little of its chemistry is known. Poly(carbon diselenide) is obtained as a black powder by thermal polymerization or photopolymerization of carbon diselenide. The obtained polymer is highly disordered, and it has a head-to-head polymer structure". 

Now we know that such model is very simplified, because these resistors are non-linear and the partial conductivities depend on the applied current [7]. However, even this simplified model turned to be very useful—first of all, for the development of electrolytic processes for production of metals from chalcogenide (mainly poly sulphide) ores. Evidently, for the successful electrowinning of such metals as Sb, Tl, In, Cu, Ag and others from its sulphide, selenide or telluride compounds, the electronic (both semiconductor and metallic) conductivity must be suppressed. For that purpose. Prof. Velikanov proposed and realised, together with his numerous scholars, the additions of compounds with pure ionic conductivity, such as sulphides of sodium and potassium. By studying the conductivities in many binary molten systems, he was able to choose the optimal compositions with high... 

Prince et al. [210] found that under dry conditions formaldehyde reacts with sodium selenide to form poly(methylene diselenide) ... 

After standing for several days at rocrni lemperature, the poly(trimeth ne diselenide) slowly precipitated out from the solution. Poly(trimethylene selenide) on degradation also forms the diselenide polymer with the evolution of propylene (Eq. 78) [212]. 

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