Whereas the first entry from Apr. 2008 were limited to the ground vibrational state, the present one takes into account data associated with higher vibrational states as well. Note, however, that the present entry is still limited to v = 0; two additional entries contain v = 1 and 2 (047519) and v = 3 – 5 (047520). The majority of the rotational data were taken from
(1) S. Bailleux, M. Bogey, C. Demuynck, Y. Liu, and A. Walters; 2002, J. Mol. Spectrosc. 216, 465.
Additional v = 0 data were provided by
(2) K. Kawaguchi, S. Saito, and E. Hirota; 1983, J. Chem. Phys. 79, 629.
Two v = 3 transition frequencies from (1) with large residuals were omitted. Also included were v = 1 – 0 data from
(3) J. E. Butler, K. Kawaguchi, and E. Hirota; 1983, J. Mol. Spectrosc. 101, 161;
and from
(4) H. B. Qian; 1995, J. Mol. Spectrosc. 174, 599.
Two vibrational correction terms, the ground state spin-orbit parameter and its second vibrational correction were taken from
(5) R. D. Verma and S. R. Singhal; 1975, Can. J. Phys. 53, 411.
The set of spectroscopic parameters differs considerably from that in (1). Data with experimental uncertainties of 1 MHz were not merged. The predictions should be reliable up to 1 THz and still reasonable at higher frequencies.
Concerning Hund's case a quantum numbers, levels with J + 0.5 = N correlate with ²Π_1/2 and levels with J – 0.5 = N correlate with ²Π_3/2 for J ≤ 11.5; the correlation is reversed for J ≥ 12.5.
The ground state dipole moment was determined by
(6) H. Kanata, S. Yamamoto, and S. Saito, 1988, J. Mol. Spectrosc. 131, 89.