MW and FTFIR transitions of {sup 13}CH{sub 3}OH revisited and review of MW spectra of CH{sub 3}OH and {sup 13}CH{sub 3}OH of astrophysical interest

Conference · Tue Dec 31 04:00:00 EST 1996

OSTI ID:437209

Xu, Li-Hong ^[1]; Walsh, M S; Lees, R M ^[2]

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1. Univ. of New Brunswick, Saint John (Canada)
2. Univ. of New Brunswick, Fredericton (Canada); and others

Microwave (MW), millimeter-wave (MMW) and Fourier-transform far-infrared (FTFIR) transitions in the first two torsional states (v{sub t} = 0 below the barrier and v{sub t} = 1 straddling the barrier) of the ground vibrational state of C-13 methanol have been globally treated and successfully fitted to within assigned measurement uncertainties using a program (I. Kleiner and M. Godefroid private communication) originally designed for acetaldehyde (CH{sub 3}CHO) based on the formalism of Herbst et al. The {sup 13}CH{sub 3}OH data set (v {sub t} {le} 1, J {le} 20, K{sub max} {le} 14) contains 725 MW and MMW lines, assigned a {+-}50 kHz measurement uncertainty apart from a few K-doublet lines, and 6283 FTFIR lines each assigned an uncertainty of {+-}0.0002 cm{sup -1} = {+-}6 MHz. A very satisfactory convergent fit has been achieved using 55 adjustable and 2 fixed parameters, yielding an overall weighted standard deviation of 0.962. Calculations employing the parameters from the final fit reveal possible C-13 assignments for 28 lines appearing in natural abundance in the newly-measured methanol microwave atlas from 7 to 200 GHz compiled by the group of K. Takagi at Toyama University.

• OSTI ID: 437209
• Report Number(s): CONF-9606118--
• Country of Publication: United States
• Language: English

Related Subjects

40 CHEMISTRY
ABSORPTION SPECTROSCOPY
CARBON 13
COMPUTER CODES
LABELLED COMPOUNDS
METHANOL
MICROWAVE SPECTRA
SPECTROSCOPY