High-resolution of the study of the [nu][sub 3] band of chlorofluoromethane by diode laser spectroscopy

Journal Article · Tue Jun 01 04:00:00 EDT 1993 · Journal of Molecular Spectroscopy; (United States)

DOI:https://doi.org/10.1006/jmsp.1993.1144· OSTI ID:6433294

Baldacci, A; Stoppa, P; Giorgianni, S; Visinoni, R; Ghersetti, S ^[1]

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1. Univ. di Venezia (Italy)

The gas-phase infrared spectrum of natural CH[sub 2]FCl has been investigated in the [nu][sub 3] region between 1,336 and 1,365 cm[sup [minus]1], at a resolution of 0.002 cm[sup [minus]1], using a tunable diode laser spectrometer. This vibration of A[prime] symmetry species is expected to give origin to an a/b-type hybrid band with a structure approaching that of parallel and perpendicular bands of a prolate symmetric top. The rovibrational analysis led to the identification of more that 1,300 (J [le] 41, K[sub a] [le] 17) and 700 (J [le] 42, K[sub a] [le] 11) transitions of the CH[sub 2]F[sup 35]Cl and CH[sub 2]F[sup 37]Cl[nu][sub 3] band centered at 1,353.3173 and 1,353.1962 cm[sup [minus]1], respectively. From a simultaneous fit of GSCD of this work, together with literature microwave measurements, a set of ground-state constants up to the quartic coefficients has been obtained using the Watson's A-reduction Hamiltonian in the I[sup 2] representation. A number of K[sub a] subbands of the main species were found to be affected by Coriolis-type resonance, and the [nu][sub 6] + [nu][sub 9] vibrational level was identified as the perturber. A least-squares fit of the assigned transitions provided a set of effective upper-state constants for both the isotopomers. From spectral simulation it was found that the [nu][sub 3] band of CH[sub 2]F[sup 35]Cl is composed of about 80 and 20% a- and b-type components, respectively.

• OSTI ID: 6433294
• Journal Information: Journal of Molecular Spectroscopy; (United States), Journal Name: Journal of Molecular Spectroscopy; (United States) Vol. 159:2; ISSN JMOSA3; ISSN 0022-2852
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
540120* -- Environment
Atmospheric-- Chemicals Monitoring & Transport-- (1990-)
AIR POLLUTION MONITORING
ATMOSPHERIC CHEMISTRY
CHEMISTRY
CHLOROFLUOROCARBONS
DETECTION
ENERGY LEVELS
ENERGY-LEVEL TRANSITIONS
EXCITED STATES
HAMILTONIANS
INFRARED SPECTRA
LAYERS
LEAST SQUARE FIT
MATHEMATICAL OPERATORS
MAXIMUM-LIKELIHOOD FIT
MONITORING
NUMERICAL SOLUTION
ORGANIC CHLORINE COMPOUNDS
ORGANIC COMPOUNDS
ORGANIC FLUORINE COMPOUNDS
ORGANIC HALOGEN COMPOUNDS
OZONE LAYER
QUANTUM OPERATORS
ROTATIONAL STATES
SPECTRA
TRACE AMOUNTS
VIBRATIONAL STATES