Emission spectra of CF3 radicals. II. Analysis of the UV emission spectrum of CF3 radicals

The spectra of the UV emission bands of the CF3 radicals produced by the photolysis of CF3H by the argon resonance lines and by the reaction of CF3H with metastable Ar atoms were analyzed. Most of the bands were identified to be the combination of the ν″1 and ν″2 vibrational modes. The energies of the v″1 and v″2 vibrational levels of the ground state CF3 are A progression having about 804 cm−1 separation was observed and assigned to the ν′1 mode in the upper excited state. The system origin of the UV emission bands was calculated to be 6.41 eV. Since the 0–12 transition was strongest in the (0–v″) progression of the ν″1 mode, the geometry of the electronically excited state should differ from that of the ground state. Further, since only the total symmetric modes (ν1 and ν2 modes) were observed, the geometry of the upper emitting state may be D3h or C3v structure. High vibrational excitation up to v′1=7 was observed in the photolysis of CF3H by the Ar lamp. The energy of the excitation agrees well with the available excess energy in the photodecomposition process.