ROTATIONAL ANALYSIS OF THE NU(1) BAND OF TRICHLOROFLUOROMETHANE FROM HIGH-RESOLUTION FOURIER-TRANSFORM AND DIODE-LASER SPECTRA OF SUPERSONIC JETS AND ISOTOPICALLY ENRICHED SAMPLES
M. Snels et al., ROTATIONAL ANALYSIS OF THE NU(1) BAND OF TRICHLOROFLUOROMETHANE FROM HIGH-RESOLUTION FOURIER-TRANSFORM AND DIODE-LASER SPECTRA OF SUPERSONIC JETS AND ISOTOPICALLY ENRICHED SAMPLES, The Journal of chemical physics, 103(20), 1995, pp. 8846-8853
The spectrum of CCl3F (trichlorofluoromethane, CFC 11) has been measur
ed in the region of the nu(1) fundamental (1050-1120 cm(-1)) by high r
esolution interferometric Fourier-transform spectroscopy [0.004 cm(-1)
bandwidth full width at half maximum, apodized] and by diode laser sp
ectroscopy (bandwidth 0.0008-0.0020 cm(-1) FWHM) at room temperature,
in cold cells and in supersonic jet expansions. Fourier-transform infr
ared and diode laser spectra of isotopically pure (CCl3F)-Cl-35 have b
een recorded at room temperature in static cells. The (CCl3F)-Cl-35 sp
ectra allowed an analysis of the rotational structure to be started su
ccessfully for the first time, The rotational analysis of the isotopic
species (CCl2ClF)-Cl-35-Cl-37 and (CClCl2F)-Cl-35-Cl-37, which are as
ymmetric rotors, was initiated from diode laser spectra of natural CCl
3F with a rotational temperature of about 20 K (5% seeded in He) resul
ting from expansion in a supersonic pulsed slit jet. The rotational an
alysis yielded effective Hamiltonian constants including accurate band
centers for the three most abundant isotopomers (CCl3F)-Cl-35 (nu(1)
= 1081.2801 cm(-1) (CCl2ClF)-Cl-35-Cl-37 (nu(1) = 1080.7330 cm(-1)), a
nd (CClCl2F)-Cl-35-Cl-37 (nu(1)=1080.0663 cm(-1)), excited state rotat
ional constants, and for (CCl3F)-Cl-35, quartic centrifugal distortion
constants. The results are important for and discussed in relation to
simulations of atmospheric absorption, line coincidences with CO2 las
ers for sub-Doppler spectroscopy, as well as IR multiphoton excitation
and infrared laser chemistry. (C) 1995 American Institute of Physics.