The experimental frequencies have been reported by
(1) G. M. Plummer, D. Mauer, K. M. T. Yamada, and K. Möller, 1988, J. Mol. Spectros. 130, 407.
With respect to the Mar. 2005 entry, additional lines up to 900 GHz have been included. They were taken from
(2) H. Spahn, H. S. P. Müller, T. F. Giesen, J.-U. Grabow, M. E. Harding, J. Gauss, and S. Schlemmer, 2008, Chem. Phys. 346, 132.
The predictions should be reliable throughout.
The ¹⁴N or D hyperfine splitting has not been considered in the present entry. Note: The partition function does not include vibrational contributions. However, information on vibrational contributions to the partition function is available.
The dipole moment was taken from
(3) B. Coveliers, W. K. Ahmed, A. Fayt, and A. G. Maki, 1990, J. Mol. Spectrosc. 142 148.