Chalcogen compounds cationic species

Chalcogenides, 5 94-96 berkelium, 28 49, 53-54 lattice energies of, 1 192, 193 ligands, 45 16 Chalcogen(II) compounds binary halides, 35 274—280 complexes with Lewis bases, 35 293-295 halo-chalcogenates(ll), 35 280-288 mixed-valence compounds, 35 288-293 cationic species, 35 291-293... 

Se2Br5", as the first reported example of a novel dinuclear cationic halogen-chalcogen species (which is treated here, probably rather arbitrarily, under the heading of mixed-valence compounds ), was prepared as the deep-purple crystalline hexafluoroarsenate from the following two different reactions in liquid SO2 59, 321) ... 

Some preliminary results on the electrochemical behaviour of elemental sulphur (and selenium) in AlCla-NaCl melts have been reported. The results for both elements were difficult to interpret, due in part to the low solubility of both elements in the melt and the modification of the electrode surfaces by the products of electrode reactions. In basic melts it was suggested that an cation is formed, in agreement with spectral studies. In acidic melts the results were more complex, and no exact conclusions could be drawn as to the nature of the species. A spectrophotometric study of the reactions of sulphur, selenium, and tellurium with aqueous solutions of NaOH at 150 °C (S, Se) and 300 °C (Te) has been carried out. From the experimental data the formation of the chain-like structure of polychalcogenide compounds was presumed. The spectra confirmed previous results concerning the mechanism of interaction of elemental chalcogens with aqueous NaOH solutions. 

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