With respect to the first entry from Dec. 2001, the data set was reevaluated. The majority of the lines (in the millimeter wavelength region) were again taken from
(1) S. Yamamoto, S. Saito, K. Kawaguchi, N. Kaifu, H. Suzuki, and M. Ohishi, 1987, Astrophys. J. 317, L119.
Additional submillimeter data were taken from
(2) J. Tang and S. Saito, 1995, J. Mol. Spectrosc. 169, 92.
The uncertainties of 10 kHz were assigned on the basis of the partial rms errors and reported standard errors in (1) and (2). The J" = 2 to 4 transition frequencies originate from
(3) N. Sakai, S. Takano, T. Sakai, S. Shiba, Y. Sumiyoshi, Y. Endo, and S. Yamamoto, 2013, J. Phys. Chem. A 117, 9831.
The J" = 0 and 1 transition frequencies were taken from
(4) Y. Oshima and Y. Endo, 1992, J. Mol. Spectrosc. 153, 627.
The uncertainties in (4) were estimated based on the residuals.
Predictions beyond 640 GHz should be viewed with caution.
The dipole moment is from
(5) R. D. Suenram and F. J. Lovas, 1994, Astrophys. J. 429, L89.