Rovibrational analysis of the v1 fundamental of CF3Cl from diode laser spectra in a supersonic slit-jet expansion

Spectra of the ν1 fundamental band of CF3Cl (CFC-13), with natural isotopic abundance, were recorded with a tunable diode laser spectrometer in the range 1100–1116 cm−1 using a supersonic pulsed slit-jet expansion. A rotational temperature of about 50 K was reached and a significant simplification of the spectra was achieved. The reduced Doppler broadening obtained using the slit source led to a FWHM up to 0.0007 cm−1 and so it was possible to resolve almost completely the K-structure in the P(J) and R(J) clusters for the first time. From the final fit of the assigned transitions a reliable set of molecular constants including the quartic centrifugal distortion coefficients for the v1 = 1 state of CF335Cl and CF337Cl has been obtained.