Chalcogen adducts

E = S, Se X = I, Br) cation.20 Whether this cation really forms in solutions, especially in low-polar solvents, is difficult to prove. It has been shown, however, that the calculated NBO charge distribution on [LE-X]+ can be of great help in predicting the most likely product, at least among [LE-EL]2+ dications, C.-T. spoke , and T-shaped hypervalent adducts.21,22 In fact, these three types of products can formally derive from a nucleophilic attack of the appropriate nucleophile on the [LE-X]+ cation at the chalcogen or the halogen site. 

In this chapter we will not attempt to give an overview of all of the knowledge on the reactivity of chalcogen-donor molecules towards di- and inter-halogens, since some aspects of this are discussed in other chapters. Instead, this chapter is dedicated exclusively to the analysis of the chemical bond and structural features of C.-T. adducts between LE chalcogen-donor molecules (E = S, Se) and di- and inter-halogens, and their reactivity towards metal powders. 

More complicated structural situations are observed in di-halogen-rich adducts of chalcogen-donor molecules when further soft-soft halogen halogen interactions intervene, thus generating multidimensional networks (see Chapter 13.1). A clear example is represented by the structure of the compound (dithizone)2 7I2 46 Based on structural data the authors have described the repeating unit in this polymeric compound as a... 

Arsenic pentachloride, instability of, 7 7-8 Arsenic pentafluoride, 7 2, 4, 5 chalcogen(IV) compound adducts, 35 259-261... 

The adducts 579 are obtained by direct (immediate) interaction (3.19) of chalcogen-ethers 578 - thioethers (Sect. 2.2.4.5), their selenium (Sec. 2.2.4.6), and tellurium (Sec. 2.2.4.7) analogues with metal salts ... 

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