Far Infrared Laser Magnetic Resonance Detection of CF3, CHF2, and CH2F

Far infrared laser magnetic resonance (FIR-LMR) spectra of CF₃, CHF₂, and CH₂F radicals were observed in the 300–800 μm wavelength region in the reactions of F atoms with a series of different hydrocarbon and partially fluorinated hydrocarbon molecules. To identify the carriers of the observed resonance patterns and to exclude or identify contamination of the spectra by additional resonances from other paramagnetic species, numerous chemical tests were developed and performed. With optimized sources and the chemical tests in hand, many spectra could be unambiguously attributed to CF₃, CHF₂, and CH₂F, respectively. The present study reports the first gas phase detection of CHF₂ radicals in their ground electronic state.