Chalcogenide Melts

It is evident that similar sets of multiple-phase transitions are bound to be observed in the respective melts. Such structural studies on the oxide melts have not yet been carried out, which is because of greater experiment complexity. Nevertheless, the chalcogenide melts, which experience structural transformations at more moderate temperatures and pressures, give examples of multiple phase transitions. Thus, the AsS [29] and CdTe [130] melts feature at least two pressure-induced transitions accompanied by a change in the short-range order structure and properties of the liquids. 

Velikanov AA (1971) Electrochemical investigation of chalcogenide melts. Dr of Sciences Thesis. Institute of General and Inorganic Chemistry, Kiev... 

Further development of Velikanov s concept of the PFC proved its usefulness not only for electrolysis of chalcogenide melts. For example, representation of the oxide film on a metal surface as PFS easily explains the Tamman s parabolic law for growth of such film in the air corrosirMi process of metals. Formation of a film of intermediate compounds on the surface of electrode explains many regularities of long-term electrolysis of the melts cmitaining compounds of polyvalent metals (see [7] for more details). 

The gallium chalcogenide halides are hygroscopic compounds that decompose (without melting) at temperatures between 240 and 380°C to a mixture of chalcogenide and halide (see Table XVIII). The tel-luride halides are yellow, and the other compounds are colorless 160, 165). 

Schmidt KH, Bottazzi P, Vannucci R, Mengel K (1999) Trace element partitioning between phlogopite, clinopyroxene, and leucite lamproite melt. Earth Planet Sci Lett 168 287-299 Shaimon RD (1976) Revised effetive ionic radii and systematic studies of interatomic distances in halides and chalcogenides. Acta Cryst A32 751-767... 

From a chemical point of view, 5 f electrons will participate in the chemical bond as evidenced by their very high melting points when one compares them with the ones of lanthanide pnictides and chalcogenides. 

Both reactive and nonreactive molten salts can be used in nontopochemical routes. An example of a nontopochemical route to inorganic materials utilizing reactive molten salts is when a metallic element is reduced in a low-melting alkali metal polychalcogenide (hiQn, where Q = O, S, Se, Te) to form a ternary metal chalcogenide. Potassium bismuth sulfide (KBi3Ss) has been prepared in... 

The most interesting glass compositions are derived from the elements of gronps 6 and 7 of the periodic table, that is, the oxides, chalcogenides, and hahdes. A very specific class of vitreons materials is represented by a new family of noncrystalline solids, the so-called metglasses or metallic glasses their prodnction is special in the sense that they require very rapid quenching of an alloy melt. 

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