Selenium and Tellurium Fluorides

For comparative purposes and in order to enhance our understanding of trends in chemical shifts, typical examples of hypervalent selenium and tellurium fluorides are provided in Scheme 7.20. 

Chemistry of selenium and tellurium fluorides is well summarized in the literature.8,9 SeF2, FSeSeF, and Se = SeF2 have been prepared in minute... 

All of these compounds are stable gases, exhibiting the maximum valency of the elements. They neither attack glass nor decompose spontaneously. The selenium and tellurium fluorides attack mercury making it adhere to glass, and m this respect they resemble (worn. Sulphur hexafluoride does not do this. 

The range of known selenium and tellurium fluorides includes many examples similar to sultur but important differences are found, with Se and Te often adopting higher coordination numbers (Table 11). No lower fluorides are known except the nnstable species FSeSeF, Se=SeF2, and SeF2. 

Engelbrecht, A. Sladky, F., "Selenium and Tellurium Fluorides," Adv. Inorg. Chem. Radiochem. 1981,24, 189. 

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