Broadband Translent Infrared Laser Spectroscopy of Trlfluorovhryl Radical , C 2 F $ Experimental and ab Inltio Results

The trifluorovinyl radical (C2F3’) is identified by using infrared spectroscopy. Real-time broadband infrared laser and diode infrared laser absorption spectra of the trifluorovinyl radical were measured. The radical was generated from UV laser photolysis of trifluoroiodoethene (C2F,I) at 248 nm in the gas phase. The observed vibrational frequencies and intensities [u,, 1290 (f5) cm-I, 106 (f39) km mol-I; and u3. 1225 ( * 5 ) cm-I, 119 (f41) km mol-I] are in good agreement with ab initio values calculated in this work. Pseudo-first-order decay kinetics of the transient vibrational bands were observed. Analysis of the photoproducts with Fourier transform infrared spectroscopy showed that 1,3-hexafluorobutadiene (C,F6) was present in high concentration. It was probably formed from the reaction of trifluorovinyl radical with trifluoroiodoethene, as is consistent with the observed kinetics.