The two lowest rotational transitions were recorded with HFS splitting caused by both ¹⁴N nuclei by
(1) C. A. Gottlieb, A. J. Apponi, M. C. McCarthy, P. Taddeus, and H. Linnartz, 2000, J. Chem. Phys. 113, 1910.
Transition frequencies without HFS splitting were taken from
(2) T. Amano and F. Scappini, 1991, J. Chem. Phys. 95, 2280,
and from
(3) G. Cazzoli, C. Degli Esposti, and F. Scappini, 1992, J. Chem. Phys., 97, 6187.
Predictions should be sufficiently reliable for all radio astronomical observations. They should be viewed with some caution beyond 600 GHz.
¹⁴N hyperfine splitting can be resolved at low quantum numbers. Therefore, a separate calculation with ¹⁴N hyperfine splitting is provided up to J" = 5 together with partition function values.
The dipole moment is from a calculation by
(4) P. Botschwina and P. Sebald, 1990, Chem. Phys. 141, 311.