Chalcogen-containing

The nomenclature used for phosphorus chalcogen containing molecules is often inconsistent in the literature, with several different naming schemes in current use. Hence for clarity, the naming system employed for the main chalcogen-phosphorus compounds in this chapter is detailed in Figure 1. 

The structural parameters describing the geometry of di-/inter-halogens binding to chalcogen-containing molecules (thioethers, selenoethers, thiocar-bonyl, and selenocarbonyl compounds) are defined in Figure 1. 

Thiophene and its derivatives, however, have become the most-studied chalcogen-containing monomers. Doped (oxidised) PT is highly conducting, and 3-alkyl-substituted PTs are soluble, easily characterised polymers,83 85 see Figure 7. Self-assembly is an important consideration in these substituted PTs, allowing control of the degree of planarity, n-orbital overlap, and hence optical... 

In this section, we look more closely at what effect the chalcogen atom has on the properties of the molecular conductors we describe. We do not attempt to review exhaustively all the chalcogen-containing components in electroactive systems, to do so would be a colossal task. Instead, carefully chosen examples and studies illustrate how chalcogen chemistry is used in the design and manipulation of electroactive materials, and ultimately how it effects suitability for molecular device applications. 

Let us consider chalcogen-containing ion-radicals. Scheme 6.22 represents three typical cases. 

Interaction of chalcogen-containing heterocycles 580 (E = S, Se, Te) with metal salts yields molecular complexes of the type 581 (3.20) ... 

Additionally to 640 (Y = S), thioarylhydrazones of salicylaldehydes 652 are applied to obtain binuclear complexes with chalcogen-containing bridge by the method above [125] ... 

The metal-exchange method is especially widely used in syntheses of chelate complexes starting from the ligands, which are low-stable in free state. Such ligands are, in particular, chalcogen-containing organic compounds. On the basis of their... 

Molybdenum coordination has recently been comprehensively reviewed in Comprehensive Coordination Chemistry, particularly in the areas of mononuclear complexes, polyoxometaUate synthesis, structure, and reactivity see also Polyoxometalates), and in chalcogen-containing cluster complexes. ... 

The noncrystalline chalcogen-containing materials can be distinguished according to the nature of the accompanying elements. As presented in Table 2, four general families of glasses can be identified. 

The reaction between phosphorus ylides and elemental sulfur or selenium has been used to prepare chalcogen-containing heterocyclic species. For example. 

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