Inequivalent C--H oscillators of gaseous alkanes and alkenes in laser photoacoustic overtone spectroscopy

Journal Article · Thu Jul 15 00:00:00 EDT 1982 · J. Chem. Phys.; (United States)

DOI:https://doi.org/10.1063/1.443925· OSTI ID:5288145

Wong, J S; Moore, C B

The overtone spectra of the C--H stretching vibrations of several gaseous alkanes and alkenes were observed using laser photoacoustic spectroscopy. Resolvable peaks are seen for each chemically or sterically equivalent C--H bond and are assigned using the local mode model. The fifth overtone transition energies decrease linearly with increasing C--H bond lengths. Spectral shifts corresponding to 0.001 A bond length differences are observed. Linear correlations of bond length and anharmonicity with fundamental C--H stretching frequency allow a Morse potential for CH bonds to be defined in terms of a single parameter. The integrated cross section per C--H oscillator for the fifth overtone spectra varied mostly within a factor of 2 about the average value of (1.08 +- 0.28) x 10/sup -23/ cm/sup 2/ cm/sup -1/.

• Research Organization: Department of Chemistry, University of California, Berkeley, California 94720
• OSTI ID: 5288145
• Journal Information: J. Chem. Phys.; (United States), Journal Name: J. Chem. Phys.; (United States) Vol. 77:2; ISSN JCPSA
• Country of Publication: United States
• Language: English

Related Subjects

640302* -- Atomic
Molecular & Chemical Physics-- Atomic & Molecular Properties & Theory
74 ATOMIC AND MOLECULAR PHYSICS
ALKANES
ALKENES
ENERGY LEVELS
ENERGY-LEVEL TRANSITIONS
EXCITED STATES
FLUIDS
GASES
HYDROCARBONS
INFRARED SPECTRA
LASER SPECTROSCOPY
MORSE POTENTIAL
ORGANIC COMPOUNDS
OSCILLATION MODES
PHOTOACOUSTIC SPECTROSCOPY
POTENTIALS
SPECTRA
SPECTROSCOPY
VIBRATIONAL STATES