IR absorption spectra of hexafluorobenzene anions and pentafluorophenyl radicals in solid argon

Hexafluorobenzene anions (HFB^-) and pentafluorophenyl radicals (PFP) were generated by the electron bombardment of a HFB/Ar sample during matrix deposition. Further irradiation of the matrix sample at 365 nm detached the electron from HFB^- and produced its neutral counterpart HFB in solid Ar. Secondary photolysis of the matrix sample at 160 nm destroyed HFB and generated HFB^- and PFP. In a separate experiment, the photolysis of the HFB/Ar matrix at 160 nm produced PFP, Dewar-C₆F₆, and various neutral fluorocarbon species, but without the production of HFB^-. The infrared (IR) lines of HFB^- and PFP were assigned on the basis of the observed photochemical behaviors, as well as by comparing the predictions of the vibrational wavenumbers with the corresponding IR intensities and the relative stabilities of the related species predicted via the B3LYP/aug-cc-pVTZ theory.