Trifluoromethyl Fluorosulfonate (CF₃OSO₂F) and Trifluoromethoxy Sulfur Pentafluoride (CF₃OSF₅) – Two Gaseous Sulfur(VI) Compounds with Insulating Properties

Abstract

In this work, we analyzed trifluoromethyl fluorosulfonate (CF3OSO2F) and trifluoromethoxy sulfur pentafluoride (CF3OSF5) regarding their potential use as dielectrics by investigating some of their intrinsic and extrinsic properties. Both compounds show a higher breakdown voltage than SF6 with averaged relative breakdown voltages of 1.3 ±0.2 for CF3OSO2F and 1.4 ±0.2 for CF3OSF5 compared to SF6 with 1.0. Like the dielectric (CF3)2CFCN, both compounds decompose during the breakdown process. The decomposition products were analyzed by IR spectroscopy and GCIR methods. Furthermore, the molecular structures of both gaseous compounds CF3OSO2F and CF3OSF5 have been determined by in situ crystallization, and their physical properties were determined as well.