Identification of radiolytic products of [C 4 mim][PF 6 ] under γ-irradiation

The trace water-soluble radiolytic products of neat 1-butyl-3-methylimidazolium hexafluorophosphate ([C4mim][PF6]) were identified by analysing water-washed samples of -irradiated ionic liquids. HF and difluorophosphinic acid were confirmed as the main radiolytic products of [C4mim][PF6], and their radiation chemical yields were quantified by 19F NMR (G(F-) = 0.14 mol/J, G(HOP(O)F2) = 0.053 mol/J). Compared to [C4mim][NTf2], [C4mim][PF6] shows better radiation stability.