The experimental frequencies have been reported by
(1) P. D. Mallinson and A. Fayt, 1976, Mol. Phys. 32, 473.
One line was omitted from the fit because of a large residual. Predictions should be reliable throughout. The precision of the IR transitions is about 0.005 cm^–1, the absolute accuracy is about 0.010 cm^–1.
An investigation has been published with about one order of magnitude better precision, but without any published transition frequencies this work is unfortuanately useless for us.
Apr. 2012: The quoted dipole moment has been corrected, and it was used. The transition dipole moment was derived from intensity measurements by
(2) 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.