The data set was replaced entirely with respect to the first entry from Dec. 2008. The linelist is based on the one provided by
(1) A. J. Remijan, Z. T. P. Fried, I. R. Cooke, G. Wenzel, R. Loomis, C. N. Shingledecker, A. Lipnicky, C. Xue, M. C. McCarthy, and B. A. McGuire, 2024, Astrophys. J. 976, Art. No. 105.
The paper present a small number of accurate microwave transition frequencies. The data set also includes oart of the microwave to millimeter wave data fromby
(2) A. Jabri, L. Kolesniková, E. R. Alonso, I. León, S. Mata, and J. L. Alonso, 2020, J. Mol. Spectrosc. 372, Art. No. 111333;
as well as millimeter wave data truncated after K_a = 14 from
(3) E. G. Robertson, M. Ruzi, D. McNaughton, L. Margulès, R. A. Motiyenko, and J.-C. Guillemin, 2023, J. Mol. Spectrosc. 394, Art. No. 111786.
Uncertainties from (3) and the part used from (2) appear to be judged conservatively, the were assumed to be 2σ values. Among the data from (2) not used in (1), there were several transitions with low K_a displaying larger residuals. Therefore, these data were not used in this compilation as well.
As indicated in (3), the ground vibrational state is perturbed somewhat at K_a = 10 and more severely at K_a = 14 and some higher ones. Therefore, calculations with K_a = 10 and 14 should be viewed with some and great caution, respectively. Calculations with uncertainties larger than 0.2 MHz should also be viewed with caution.
The dipole moment was reported in
(4) R. D. Brown and P. D. Godfrey, 1984, Aust. J. Chem. 37, 1951.