The transition frequencies were summarized by
(1) O. Desyatnyk, L. Pszczółkowski, S. Thorwirth, T. M. Krygowski, and Z. Kisiel, 2005, Phys. Chem. Chem. Phys. 7, 1708.
Predictions with uncertainties larger than 0.15 MHz should be viewed with caution. This is probably not of importance for astronomical observations.
The dipole moment was determined in (1).