The J" = 0 and 1 transition frequency were reported in
(1) F. Matsushima, T. Oka, and K. Takagi, 1997, Phys. Rev. Lett., 78, 1664.
Additional rotational transitions have been measured with accuracies of about 150 MHz or somewhat better. J" = 6 was recorded by
(2) D. J. Liu, W. C. Ho, and T. Oka, 1987, J. Chem. Phys. 87, 2442.
J" = 10 – 18 were taken from
(3) Z. Liu and P. B. Davis, 1997, J. Chem. Phys. 107, 337.
Transition frequencies from (2) and (3) have not been merged. The transitions should deviate from the predictions by less than three to five time the uncertainties because of the extensive input data set.
A ground state dipole moment value was published in
(4) M. Pavanello, S. Bubin, M. Molski, and L. Adamowicz, 2005, J. Chem. Phys. 123, Art. No. 104306.