Sulfur, Selenium, and Tellurium Fluorides

Sulfur tetrafluoride appears as two broad singlets at RT, as one broad singlet at 85 °C, and (when dry) as two sharp triplets at -30 °C. SF6, with its symmetrical octahedral geometry, appears as a sharp singlet at all temperatures. The activation energy for pseudorotation of SF4, which interconverts its axial and equatorial fluorines, is 12 kcal/mol.4 

Fluorination of diaryl sulfides, selenides, and tellurides leads to the formation of diarylsulfur, selenium, and tellurium difluorides, all of 

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