Polyatomic chalcogen dications

The inorganic dications display electrophilic and oxidative properties, but are much more reactive. For example, all cluster chalcogen dications are rapidly hydrolyzed even by the traces of water.159 

The presence of free radicals in solutions of the S82+ dication has been known for a long time. Initially, S4+ was detected by ESR, and its formation 

In summary, the combination of experimental results and theoretical advances described in this work suggests that chalcogen dications, which have been considered for a long time as hypothetical or ephemeral intermediates can be used in a variety of chemical transformations. Unusual structures of these compounds impart them with reactivities that are remarkably different from other organic intermediates. Harnessing this reactivity should lead to interesting practical applications and we foresee rapid development of this field in the future. 

Frenking and D. Cremer, Structure and Bonding, vol 73, Springer, Heidelberg, 1990, 17 95. 

Breslow and H. Skolnik, The Chemistry of Heterocyclic Compounds, vol 21, Interscience, New York, 1966. 

Polyatomic dications of sulfur, selenium and tellurium were discovered at the end of the 1960s during the investigation of intensively colored solutions known for almost a century. These solutions are formed when chalcogens are dissolved in concentrated sulfuric acid or oleum.The first dications studied by X-ray crystallography were a hydrosulfate of tetraatomic selenium dication (Se4 ) and tetrachloroaluminates of octaatomic selenium dication (Seg ) and tetraatomic tellurium dication ( 04 ). Up to now, a large volume of reliable 

The principal differences in the structures of organic and inorganic chalcogen 

Polyatomic chalcogen dications are typical cluster compounds.Current interpretation of chemical bonding in the Sg dication invokes formation of a weak delocalized bond as a result of overlap of six 3p orbitals of the 

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