1,3-Difluoro-trisulfane-1,1-difluoride explained

1,3-Difluoro-trisulfane-1,1-difluoride is an inorganic molecular substance with the structure SF₃SSF, consisting of sulfur in a low oxidation state with fluorine. The compound consists of a chain of three sulfur atoms, with three fluorine atoms bonded to the sulfur on one end and the fourth fluorine bonded to the sulfur on the other end. It has a melting point of -62 °C and a boiling point of 94 °C. As a gas, it is unstable and breaks up to form SSF₂ and SF₄.^[1]

SF₃SSF is produced by the condensation of sulfur difluoride and an isomer of SSF₂.^[2] The reaction S₃F₄  SSF₂ + SF₂ uses 6 kJ/mol.^[3]

Possible isomers of its S₃F₄ molecular formula include FSSF₂SF, which has a spontaneous fluorine migration to yield F₂SSSF₂, which in turn spontaneously fragments to give SF₂ and SSF₂.^[4]

Notes and References

1. Willner. Helge. Chalkogenfluoride in niedrigen Oxydationsstufen. IX. Darstellung und Charakterisierung von SF3SSF. Chalcogen fluorides in lower degrees of oxidation. IX. Preparation and characterization of 1,3-difluorotrisulfane 1,1-difluoride (SF₃SSF). Zeitschrift für anorganische und allgemeine Chemie. July 1984. 514. 7. 171–178. 10.1002/zaac.19845140721.
2. Berry. F. J. . Chapter 6. O, S, Se, Te . Annu. Rep. Prog. Chem., Sect. A: Inorg. Chem.. 1984. 81. 145. 10.1039/IC9848100137.
3. Lösking. O.. Willner. H.. Baumgärtel. H.. Jochims. H. W.. Rühl. E.. Chalkogenfluoride in niedrigen Oxydationsstufen. X Thermochemische Daten und Photoionisations-Massenspektren von SSF₂, FSSF, SF₃SF und SF₃SSF. Zeitschrift für anorganische und allgemeine Chemie. November 1985. 530. 11. 169–177. 10.1002/zaac.19855301120.
4. Jug. Karl. Iffert. Rüdiger. SINDO1 study of sulphur isomers and sulphur fluorine compounds. Journal of Molecular Structure: THEOCHEM. April 1989. 186. 347–359. 10.1016/0166-1280(89)87055-1.