Journal of Chemical Physics, Vol.105, No.9, 3406-3418, 1996
Fourier-Transform Spectroscopy of Torsionally Excited C-13 Methanol in the Co-Stretching Band
Torsionally excited n=1 and n=2 subbands of the CO-stretching fundamental have been assigned in the Fourier transform infrared spectrum of (CH3OH)-C-13 recorded at a resolution of 0.002 cm(-1). For the n=1 torsional state, subbands with K values up to 7 have been identified for A torsional symmetry and up to 5 for E symmetry. For n=2, four subbands have so far been assigned. Subband origins have been obtained by fitting the observed wave numbers to J(J+-1) power-series expansions. The expansion parameters represent the data compactly to close to the experimental uncertainty in the absence of line blending or perturbations. Significant downshifting of the n=1 origins is observed, correlated closely with proximity to the n=0 OH-bending state. J-localized perturbations have been observed and characterized for several subbands. Two of the far-infrared laser lines optically pumped by the 10R(14) CO2 laser line have been assigned.
Keywords:INFRARED-LASER LINES;HIGH-RESOLUTION SPECTROSCOPY;FIR LASER;DOUBLE-RESONANCE;(CH3OH)-C-13;SPECTRUM;ASSIGNMENTS;CH3OH;EMISSION;IDENTIFICATION