Tellurides, formation

Molybdenum hexafluoride. 3,1412 Molybdenum-iron-sulfur complexes, 4,241 Molybdenum oxide amino acid formation prebiotic systems, 6, 872 Molybdenum storage protein microorganisms, 6, 681 Molybdenum telluride, 3, 1431 Molybdenum tetraalkoxides physical properties, 2, 347 Molybdenum tribromide, 3,1330 Molybdenum trichloride, 3,1330 Molybdenum trifluoride, 3, 1330 Molybdenum trihalides, 3, 1330 bond lengths, 3, 1330 magnetic moments, 3,1330 preparation, 3,1330 properties, 3, 1330 structure, 3,1330 Molybdenum triiodide, 3,1330 Molybdenum trioxide complexes, 3, 1379 Molybdenum triselenide, 3, 143)... 

The telluride halides crystallize in monoclinic lattices, but only In-TeBr and InTel are isotypic 162). InTeCl forms a layer type of structure, as do InSCl and its analogs, but, owing to the size of the Te atom and the enhanced covalency of the In-Te bond, only a coordination number of 4 for indium is realized. The structure is built up of strongly distorted, InTesraCli/j tetrahedra that share the corners and edges occupied by Te atoms. The Cl atoms are coordinated to one tetrahedron each, and do not take part in the layer formation 324, 325). 

Finely symmetrical divinyl tellurides 135, especially useful in transmetallation reactions, have been prepared in situ by sequential reaction of an excess of the ylide 134 with TeCl4 and aldehydes (Scheme 36) [134]. These compounds whatever their geometry lead in presence of -BuLi to the formation of -a,/l-unsat-urated aldehydes. 

Dennison S, Webster S (1992) An investigation into the effect of ionic species on the deposition of tellurium and the formation of cadmium telluride. J Electroanal Chem 333 287-298... 

The induced co-deposition concept has been successfully exemplified in the formation of metal selenides and tellurides (sulfur has a different behavior) by a chalcogen ion diffusion-limited process, carried out typically in acidic aqueous solutions of oxochalcogenide species containing quadrivalent selenium or tellurium and metal salts with the metal normally in its highest valence state. This is rather the earliest and most studied method for electrodeposition of compound semiconductors [1]. For MX deposition, a simple (4H-2)e reduction process may be considered to describe the overall reaction at the cathode, as for example in... 

Anodization is facilitated at alkaline pH by the stability of low oxidation state chalcogen species (e.g., Te ) in this range. Thus, intended corrosion of a cadmium electrode in telluride environment may lead to the formation of CdTe ... 

The electrodeposition of tellurium and silver has been investigated in dilute aqueous solutions of tellurous acid and Ag " ions (concentrations in the order of 10 to 10 " M) in 0.1 M HCIO4 [164], In particular, cyclic voltammetry experiments were conducted with rotating glassy carbon disk electrodes in baths with various concentration ratios of Ag(I) and Te(IV) precursors, and their outcome was discussed in terms of the voltammetric features. For a Ag(I)/Te(IV) ratio close to 0.8, formation of quasi pure silver telluride, Ag2Te, was reported. The authors, based on their measurements and on account of thermodynamic predictions, assumed that silver is deposited first on the electrode (Ag" + e Ag), and then Te(IV) is reduced on the previous silver deposit with formation of Ag2Te according to the reaction... 

Sharma RK, Singh G, Shul YG, Kim H (2007) Mechanism of manganese (mono and di) telluride thin-film formation and properties. Physica B 390 314-319... 

Zinc telluride and zinc selenide polymetallic species with phosphine ligands have been structurally characterized 301 further details are discussed in Section 6.8.7. The use of mono- and bidentate phosphine ligands of varying steric bulk contributes to the variation of structural types in the formation of zinc tellurolate polyzinc species with Zn10, Zn14, and Zn16 species structurally characterized by Fenske et al.30... 

TMEDA can also participate in the formation of multinuclear zinc telluride complexes with Znio, Zni4, and Zni6 complexes structurally characterized. A comparison was carried out by Pfistner et al. replacing the diamine with a diphosphorus ligand, bis(diphenylphosphino)methane,... 

Equations 4 and 5 together have essentially the same result as Equation 3, oxidative UPD or the formation of a Te atomic layer. The advantage is that oxidative UPD can be accomplished using the more stable tellurite solutions, instead of unstable telluride solutions. 

Hydrogen sulfide can be prepared from the elements, but the unfavorable heat of formation of H2Se and H2Te indicates that producing them by direct combination is not a efficient route. Instead, they are first obtained as selenides and tellurides, which then react with an acid. 

Attempts to synthesise tritellurophosphonic acids or their salts have so far proved unsuccessful, and synthetic routes from primary phosphines analogous to Equation 39 with E = Te give just cyclic polyphosphanes (RP) and lithium telluride with no observed tritellurophosphonate formation.45... 

Despite facile formation of p-type ZnTe from the precursor, films of ZnTe formed from a drop cast precursor solution had a small grain structure (using conditions that we have so far explored), which limited prospective TFT device performance. Note that we expect a similar chemistry to that for ZnTe to also be operative for selected other metal telluride precursors. In contrast to the ZnTe films, well-crystallized films of In2Te3 have been formed using... 

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