High resolution FTIR spectroscopy of chlorofluoromethane near 13 micrometri: rovibrational analysis and resonances of nu5 and 2nu6 bands in CH235ClF and CH237ClF

none7noThe FTIR spectra of CH2ClF (natural isotopic mixture) and CH37 2 ClF (isotopically enriched sample) were investigated in the 5 and 26 region between 700 and 800 cm1 at a resolution of 0.004 cm1. The 5 and 26 vibrations of A0 symmetry give rise to a/b hybrid bands with a very predominant a-type component. Due to the proximity of their band origins, the v5¼1 and v6¼2 levels perturb each other by Fermi and Coriolis resonances. The interaction mechanisms, previously investigated in the rotational spectra of CH35 2 ClF, were extended to the less abundant isotopic species CH37 2 ClF and to higher J and Ka values in the main isotopologue. The spectral analysis resulted in the identification of 4188 and 5392 transitions for CH35 2 ClF and CH37 2 ClF, respectively. All the assigned data were simultaneously fitted using the Watson’s A-reduction Hamiltonian in the Ir representation and perturbation operators. Excited state parameters, band origins and coupling terms for the 5/26 dyad of both isotopologues were determined.noneStoppa P.; Baldacci A.; Pietroplli Charmet A.; Tasinato N.; Giorgianni S.; Canè E.; Nivellini G.Stoppa P.; Baldacci A.; Pietroplli Charmet A.; Tasinato N.; Giorgianni S.; Canè E.; Nivellini G