New millimeter-wave and microwave measurements for CH3OD have been combined with previous literature data and with an extended body of Fourier transform far-infrared observations in a full global analysis of the first two torsional states (v(t) = 0 and 1) of the ground vibrational state. The fitted CH3OD data set contained 564 microwave and millimeter-wave lines and 4664 far-infrared lines, representing the most recent available information in the quantum number ranges J less than or equal to 20 and K less than or equal to 15. A 53-parameter converged global fit was achieved with an overall weighted standard deviation of 1.060, essentially to within the assigned measurement uncertainties of +/- 100 kHz for almost all of the microwave and millimeter-wave lines and +/- 6 MHz for the far-infrared lines. The new parameters for CH,OD are compared to previous results obtained for the (CH3OH)-C-12, (CH3OH)-C-13, and CD3OH isotopomers over the same quantum number ranges using the identical fitting program. Strong asymmetry-induced coupling between the accidentally near-degenerate 0E and -1E v(t) = 0 substates is successfully modeled by the fit, (C) 2000 Academic Press.
Millimeter-wave spectra and global torsion-rotation analysis for the CH3OD isotopomer of methanol
MORUZZI, GIOVANNI;
2000-01-01
Abstract
New millimeter-wave and microwave measurements for CH3OD have been combined with previous literature data and with an extended body of Fourier transform far-infrared observations in a full global analysis of the first two torsional states (v(t) = 0 and 1) of the ground vibrational state. The fitted CH3OD data set contained 564 microwave and millimeter-wave lines and 4664 far-infrared lines, representing the most recent available information in the quantum number ranges J less than or equal to 20 and K less than or equal to 15. A 53-parameter converged global fit was achieved with an overall weighted standard deviation of 1.060, essentially to within the assigned measurement uncertainties of +/- 100 kHz for almost all of the microwave and millimeter-wave lines and +/- 6 MHz for the far-infrared lines. The new parameters for CH,OD are compared to previous results obtained for the (CH3OH)-C-12, (CH3OH)-C-13, and CD3OH isotopomers over the same quantum number ranges using the identical fitting program. Strong asymmetry-induced coupling between the accidentally near-degenerate 0E and -1E v(t) = 0 substates is successfully modeled by the fit, (C) 2000 Academic Press.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
