Disulfur decafluoride is a chemical compound with the formula . It was discovered in 1934 by Denbigh and Whytlaw-Gray. Each sulfur atom of the molecule is octahedral, and surrounded by five fluorine atoms and one sulfur atom. The two sulfur atoms are connected by a single bond. In the molecule, the oxidation state of each sulfur atoms is +5, but their valency is 6 (they are hexavalent).
It is a colorless liquid with a burnt match smell similar to sulfur dioxide.
Production Disulfur decafluoride is produced by photolysis of , or in H2:
Disulfur decafluoride arises by the decomposition of sulfur hexafluoride. It is produced by the electrical decomposition of sulfur hexafluoride ()—an essentially inert insulator used in high voltage systems such as transmission lines, substations and switchgear. is also made during the production of .
Properties The bond dissociation energy is , about stronger than the bond in diphenyldisulfide.
At temperatures above , decomposes slowly (disproportionation) into and sulfur tetrafluoride ():
reacts with tetrafluorohydrazine () to give difluoroamino sulfur pentafluoride ():
In the presence of excess chlorine gas, reacts to form sulfur chloride pentafluoride ():
The analogous reaction with bromine is reversible and yields . The reversibility of this reaction can be used to synthesize from .
It reacts with to form pentafluorosulfur fluorosulfonate () in the presence of ultraviolet radiation.
Ammonia is oxidised by into .
Toxicity was considered a potential chemical warfare pulmonary agent in World War II because it does not produce lacrimation or skin irritation, thus providing little warning of exposure. Disulfur decafluoride is a colorless gas or liquid with a sulfur dioxide ()-like odor. Its toxicity is thought to be caused by its disproportionation in the lungs into , which is inert, and , which reacts with moisture to form sulfurous acid and hydrofluoric acid.
See also Phosgene Perfluoroisobutene Bis(trifluoromethyl) disulfide
References