The ground and first torsional states of CD3CHO

The rotational spectra for the ground and first excited torsional states nu (t) = 0 and 1 in the frequency region of 8-254 GHz and the nu(t) = 1 <-- 0 band high-resolution far-infrared spectrum of 2,2,2-d(3)-acetaldehyde (CD3C HO) were measured. We fitted a data set consisting of 1016 nu(t) = 1 <-- 0 far-infrared lines together with 195 microwave lines in nu(t) = 0 and 79 mi crowave lines in nu(t) = 1 to near-experimental accuracy, using a global mo del from the earlier literature. The final fit includes lines with J less t han or equal to 20 and requires 25 parameters to achieve root-mean-square d eviations of 87 and 88 kHz for the microwave v(t) = 0 and 1 lines, respecti vely, and of 0.00048 cm(-1) for the far-infrared nu(t) = 1-0 lines. This ca n be considered a good starting point for future analysis of CD3CHO. (C) 19 99 Academic Press.