Quasi-cw inverse Raman spectroscopy of the. nu. /sub 1/ fundamental of /sup 13/CH/sub 4/

Journal Article · Tue Jan 15 04:00:00 EST 1980 · J. Chem. Phys.; (United States)

OSTI ID:5756626

McDowell, R S; Patterson, C W; Owyoung, A

A Doppler-limited Raman spectrum of the symmetric stretching fundamental (..nu../sub 1/) of /sup 13/CH/sub 4/ has been recorded using high-sensitivity ''quasi-cw'' inverse Raman spectroscopy. The band is very different in appearance from ..nu../sub 1/ of /sup 12/CH/sub 4/, due mainly to a much smaller value of ..delta..B for the heavier species, which causes many of the transitions to overlap near the band origin. Line assignments have been made for J< or =11. The spectroscopic constants have been determined from the frequencies of 25 resolved transitions and a computer synthesis of the largely unresolved central region. The observed /sup 12/C--/sup 13/C isotope shift, 1.04 +- 0.02 cm/sup -2/, does not agree completely with predictions based on any available set of anharmonicity constants, but it does indicate that a simplified calculation based on a Dennison-type approximation for the anharmonicity constants of isotopic species is not valid. The large difference in ..delta..B between the two species is attributed to the effect of Coriolis interaction with the nearby combination level ..nu../sub 2/+..nu../sub 4/.

• Research Organization: University of California, Los Alamos Scientific Laboratory, Los Alamos, New Mexico 87545
• OSTI ID: 5756626
• Journal Information: J. Chem. Phys.; (United States), Journal Name: J. Chem. Phys.; (United States) Vol. 72:2; ISSN JCPSA
• Country of Publication: United States
• Language: English

Related Subjects

640302* -- Atomic
Molecular &amp; Chemical Physics-- Atomic &amp; Molecular Properties &amp; Theory
74 ATOMIC AND MOLECULAR PHYSICS
ALKANES
CARBON 13
CARBON ISOTOPES
CRYOGENIC FLUIDS
EVEN-ODD NUCLEI
FLUIDS
HYDROCARBONS
ISOTOPE EFFECTS
ISOTOPES
LIGHT NUCLEI
METHANE
MOLECULAR STRUCTURE
NUCLEI
ORGANIC COMPOUNDS
RAMAN SPECTRA
SENSITIVITY
SPECTRA
STABLE ISOTOPES