The millimeter-wave spectrum of 2-cyanoethanol

In order to better characterize the chemistry involving CN groups in regions of star-formation, we have recorded the millimeter-wave rotational spectrum of 2-cyanoethanol. Almost 6000 new transitions were assigned to two separate conformers and three torsionally excited states. The lowest energy conformer, gauche-2-cyanoethanol, its 1st excited torsion, and the ground state for the anti-I-conformer are best characterized with basic asymmetric rigid-rotor Hamiltonians including distortion. All fit close to experimental uncertainty. Fits for the 2nd and 3rd excited torsional states for the gauche-conformer are of somewhat lower quality, which might be explained by a potential interaction between these states. The results of the various fits are discussed in this paper. In all, the present characterization of the spectrum and extensions through prediction should be more than sufficient to guide future millimeter-wave observational studies of this species in the interstellar medium.