High-resolution interferometric Fourier transform infrared absorption spectroscopy in supersonic free jet expansions: carbon monoxide, nitric oxide, methane, ethyne, propyne, and trifluoromethane

Journal Article · Thu Sep 22 04:00:00 EDT 1988 · J. Phys. Chem.; (United States)

DOI:https://doi.org/10.1021/j100330a025· OSTI ID:6187889

Amrein, A; Quack, M; Schmitt, U

The infrared absorption spectra of neat CO, NO, CH/sub 4/, C/sub 2/H/sub 2/, CH/sub 3/CCH, and CHF/sub 3/ in supersonic free jet expansions have been recorded at apodized resolutions of up to 0.0004 cm/sup -1/ (fwhm) and wavenumbers ranging from 1000 to 3400 cm/sup -1/. The line widths are found to be essentially Doppler limited. Rotational temperatures as low as 6 K for CO and 10-50 K for the other gases have been determined from the spectra. Electronic (NO), vibrational (CH/sub 3/CCH), and nuclear spin (CH/sub 4/, C/sub 2/H/sub 2/) relaxation is discussed as well. In those cases rotational and electronic relaxation is fast, vibrational relaxation incomplete and nuclear spin symmetry conservation perfect to within the authors accuracy. The aspect of simplification of infrared spectra and nuclear by jet cooling is investigated, in particular for the extremely complex bands of CHF/sub 3/.

• Research Organization: ETH-Zurich (Zentrum) (Switzerland)
• OSTI ID: 6187889
• Journal Information: J. Phys. Chem.; (United States), Journal Name: J. Phys. Chem.; (United States) Vol. 92:19; ISSN JPCHA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
500100 -- Environment
Atmospheric-- Basic Studies-- (-1989)
54 ENVIRONMENTAL SCIENCES
ABSORPTION SPECTROSCOPY
ALKANES
ALKYNES
CARBON COMPOUNDS
CARBON MONOXIDE
CARBON OXIDES
CHALCOGENIDES
DATA
ENERGY LEVELS
ENERGY-LEVEL TRANSITIONS
EXCITED STATES
EXPERIMENTAL DATA
FLUID FLOW
FLUORINATED ALIPHATIC HYDROCARBONS
FOURIER TRANSFORM SPECTROMETERS
HALOGENATED ALIPHATIC HYDROCARBONS
HYDROCARBONS
INFORMATION
INFRARED SPECTRA
JETS
MEASURING INSTRUMENTS
METHANE
NITRIC OXIDE
NITROGEN COMPOUNDS
NITROGEN OXIDES
NUMERICAL DATA
ORGANIC COMPOUNDS
ORGANIC FLUORINE COMPOUNDS
ORGANIC HALOGEN COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
PROPYNE
ROTATIONAL STATES
RYDBERG STATES
SPECTRA
SPECTROMETERS
SPECTROSCOPY
SUPERSONIC FLOW
VIBRATIONAL STATES