Hydrogen fluoride solvent system. Part III. Solutions of the acids SbF5, AsF5, and PF5. Evidence for the As2F11– ion

Abstract

Cryoscopic measurements on solutions of antimony pentafluoride in HF confirm that it is a strong 1 : 1 electrolyte in dilute solutions. Cryoscopic and conductimetric measurements show that arsenic pentafluoride dissolves to form the strong electrolyte H₂F⁺As₂F₁₁^–. The dimeric anion As₂F₁₁^– has been isolated as the tetraethylammonium salt. Phosphorus pentafluoride appears to be a non-electrolyte in this solvent.