Fluoroantimonic acid

Chemical compound

Fluoroantimonic acid is a mixture of hydrogen fluoride and antimony pentafluoride, containing various cations and anions, the simplest being fluoronium (H2F+) and fluoroantimonate (SbF−6). The mixture is the strongest known superacid, stronger than pure sulfuric acid by many orders of magnitude, according to its Hammett acidity function. It even protonates some hydro­carbons to afford pentacoordinate carbo­cations (carbonium ions).

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