Line Intensities of CH3D in the Triad Region: 6-10 mu m

Abstract Line intensities of the three lowest fundamentals of the 12 CH 3 D Triad are modeled with an RMS of 3.2% using over 2100 observed values retrieved by multispectrum fitting of enriched sample spectra recorded with two Fourier transform spectrometers. The band strengths of the Triad in units of 10 −18  cm −1 /(molecule cm −2 ) at 296 K are, respectively, 2.33 for ν 6 ( E ) at 1161 cm −1 , 1.75 for ν 3 ( A 1 ) at 1307 cm −1 and 0.571 for ν 5 ( E ) at 1472 cm −1 . The total calculated absorption arising from 12 CH 3 D Triad fundamentals is 4.65×10 −18  cm −1 /(molecule cm −2 ) at 296 K. In addition, some 740 intensities of nine hotbands are fitted to 8.1%; most of the hotband measurements belong to 2 ν 6 − ν 6 and ν 3 + ν 6 − ν 3 near 1160 cm −1 , 2 ν 3 − ν 3 near 1290 cm −1 and ν 3 + ν 6 − ν 6 near 1304 cm −1 . The other observed hotbands are ν 5 + ν 6 − ν 6 , 2 ν 5 − ν 5 , ν 5 + ν 6 − ν 5 , ν 3 + ν 5 − ν 3 , and ν 3 +ν 5 −ν 5 .

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