The largely millimeter wave transition frequencies were taken from
(1) C. Cabezas, K. Vávra, G. Molpeceres, L. Kolesniková, M. Agúndez, G. Vylitová, N. Marcelino, L. Hrubčík, R. Fuentetaja, T. Uhlíková, B. Tercero, J. Koucký, G. Esplugues, P. Kania, P. de Vicente, Š. Urban, and J. Cernicharo, 2025, Astron. Astrophys. 698, Art. No. L24.
Additional, largely microwave frequencies are from
(2) K. Georgiou and H. Kroto, 1980, J. Mol. Spectrosc. 83, 94.
The calculation was truncated at 500 GHz and J = 99. Calculated frequencies with uncertainties exceeding 0.1 MHz should be viewed with caution.
The experimental dipole moment of the main isotopolog is from (2). However, in the absence of experimental b-type transitions, this type of transitions can not be calculated reliably.