The rotational and rovibrational transitions were reported in
(1) J. L. Doménech, S. Schlemmer, and O. Asvany, 2017, Astrophys. J. 849, Art. No. 60.
The ab initio dipole moment was reported in
(2) H. S. P. Müller and D. E. Woon, 2013, J. Phys. Chem. A 117, 13868.
Transition frequencies should be reliable up to 2 THz, possibly higher.