“…It is well known that CHF 2 Cl contributes to ozone depletion and global warming (green house effect). The tropospheric lifetime, due to UV photolysis and oxidation by OH radicals (7), of CHF 2 Cl is about 10-30 years (1,2,(6)(7)(8); the most recent estimated lifetime is 15-20 years (9). The analysis of infrared tropospheric and stratospheric spectra is hindered by the lack of detailed spectroscopic knowledge (absorption cross sections, quantum assignments, line broadening parameters) even for the strongest bands in the atmospheric window (8-13 µm tational (and vibrational) cooling can be obtained by expanding seeded mixtures of CFC's in a supersonic jet, thus simplifying the absorption spectra.…”