The high-resolution spectrum of the ν1 (A1) band of 12CD3F

Abstract The spectrum of the ν 1 ( A 1 ) band of 12 CD 3 F has been recorded with a resolution of 0.010 cm −1 and deconvolved to 0.005 cm −1 . Over 1050 transitions have been assigned with K ≤ 16 and J ≤ 42. The spectrum is highly perturbed, exhibiting avoided crossings in most of the observed sub-bands. The origin of most of the local and global resonances has been determined and the coupling constants estimated. Due to the complexity of the spectrum resulting from the 24 potential interacting states in the region, the assigned frequencies were fitted in a restricted manner ( K ≤ 3, J ≤ 15), to obtain the following effective constants for the band: ν 0 = 2090.8118(20) cm −1 , α A = 1.19743 × 10 −2 cm −1 , and α B = −1.8489 × 10 −3 cm −1 . From an unrestricted least-squares analysis, fixing the above parameters the β's ( D v x = D 0 x − β v x ) were calculated to be β J = 1.7776 × 10 −7 cm −1 , β JK = 8.3406 × 10 −7 cm −1 , and β K = −6.3829 × 10 −7 cm −1 . These constants serve as good starting parameters for the global analysis necessary to fully analyze the 5-μm region of the 12 CD 3 F spectrum.