Absolute absorption intensities in the triad ν3, ν5, ν6 of 12CH3D at 6–10 μm

Abstract The absolute absorption intensities of 80 lines belonging to ν 3 , ν 5 , and ν 6 of 12 CH 3 D were measured in the range 1062–1480 cm −1 using a dual beam tunable diode laser spectrometer. The data were analyzed within a triad model using the energy and intensity formulation recently set up for investigating all three bands present at 6–10 μm. The fit led to the determination of the three dipole moment derivatives δμ δq s (s = 3, 5, 6) involved in the triad. Three first-order Herman-Wallis type coefficients were also required to account for the observations. All linestrengths were reproduced with an overall standard deviation of 3.4%, to be compared to an experimental uncertainty of 3.0%. The values derived for the band strengths of ν 3 , ν 5 , and ν 6 are 40.1, 13.4, and 53.2 cm −2 atm −1 , respectively, at 296 K. Comparison is made with literature data.