ESR Spectrum of FOO

Abstract

The ESR spectrum obtained during the electron irradiation of liquid CF4 containing trace amounts of oxygen consists of a 12.83‐G doublet at g=2.0038. Under the conditions of the experiments the radical producing this spectrum has a mean lifetime of ∼20 min. This observed spectrum is similar to the doublet which has been found in various oxides of fluorine. Addition of small amounts of oxygen enriched in 17O shows that the radical contains two nonequivalent oxygen atoms which have appreciable hyperfine constants. The 17O coupling constants, a O′=22.17 and a O″=14.50 G, are similar to those found in RO2·. The simplest radical which can be proposed to explain these results in FO2·. Upon prolonged irradiation the CF4 shows a second, transient spectrum which is tentatively assigned to CF3OCF2·.