Chemistry in Liquid Anhydrous Hydrogen Fluoride (aHF)

The successful generation, by precipitation out of liquid anhydrous HF, of fluorides thermodynamically unstable with respect to loss of elemental F₂, gave a forceful reminder of the remarkable stability of that solvent towards oxidation. Soon after the preparation of AgF₃, in attempts to find evidence for cationic derivatives (e.g. [AgF₂]⁺), it was discovered (see Ref. 98) that even divalent silver, as a cation, Ag²⁺ (solvated by HF), had the capability to oxidize Xe. This made chemical sense, since a cation, having an electron deficit, should have higher electronegativity than a related oxidation-state in a neutral or anionic species. Indeed, this had three important consequences…