Please note that this entry deals with the asymmetric isotopomer with one ¹³C. The transition frequencies were largely taken from
(1) M. Bogey, C. Demuynck, J. L. Destombes, and H. Dubus, 1987, J. Mol. Spectrosc. 122, 313.
Additional lines were published by
(2) S. Spezzano, F. Tamassia, S. Thorwirth, P. Thaddeus, C. A. Gottlieb, and M. C. McCarthy, 2012, Astrophys. J. Suppl. Ser. 200, Art. No. 1.
The uncertainties in (1) are overall somewhat conservative. Some higher order parameters were taken from the main spcies and were kept fixed after scaling. Predictions with uncertainties larger than 0.5 MHz should be viewed with caution.
The ¹³C hyperfine splitting has been resolved to a large degree in (2). The hyperfine splitting may be be resolvable in astronomical observations of cold sources. Therefore, a separate hyperfine calculation is provided up to J = 2 and up to 150 GHz. The partition function values include the spin-multiplicity of the ¹³C nucleus.
Note: Non-trivial spin-statistics do not matter for this low symmetry (C_S) isotopolog.
The total dipole moment was taken from the main species, see e038506.cat. The rotation of the inertial axis induces a sizable a-dipole moment component. The relative magnitude was derived in (2).