The experimental frequencies have been reported by
(1) K. M. T. Yamada, R. Best, and G. Winnewisser, 1983, Z. Naturforsch. 38a, 23.
v₃ = 1 rotational transitions were also used in the fit. They were taken from
(2) M. E. Sanz, M. C. McCarthy, and P. Thaddeus, 2005, J. Chem. Phys. 122, Art.-No. 194319.
Predictions may be reliable throughout. The precision of the IR transitions is about 0.0005 cm^–1, the absolute accuracy was not stated.
The transition dipole moment was derived from intensity measurements by
(3) A. Jolly, Y. Benilan, and A. Fayt, 2007, J. Mol. Spectrosc. 242, 46.
NOTE: The partion function refers to the ground state only ! Vibrational contributions to the partition function are available for selected states.