The experimental data was reported by
(1) E. Kim and S. Yamamoto, 2005, J. Mol. Spectrosc. 233, 93.
Because of the limited input data, predictions were limited to 300 GHz and K_a = 0. Several spectroscopic parameters have been estimated from ab initio calculations by
(2) H. S. P. Müller, 2009, unpublished.
It is advisable to view predictions even in the 3 mm region with some caution, but the predictions could also be quite reliable at considerably higher frequencies.
Spin-statistics do not have to be considered. The partition function takes into account higher values of K_a.
The dipole moment was assumed to agree with that of the main isotopic species, see e050503.cat.