Transitions frequencies without hyperfine splitting were reported in
(1) J. Cernicharo, B. Lefloch, M. Agúndez, S. Bailleux, L. Margulès, E. Roueff, R. Bachiller, N. Marcelino, B. Tercero, C. Vastel, and E. Caux, 2018, Astrophys. J. 853, L22.
The J = 2 – 1 transition frequencies with HFS splitting observed in TMC-1 were kindly provided by J. Cernicharo.
Predictions should be reliable for all observational purposes. Caution is advised for predictions with uncertainties larger than 0.1 MHz.
The ¹⁴N hyperfine splitting is resolvable at lower frequencies. Therefore, a separate calculation with hyperfine structure is available up to 251 GHz and with J" up to 4. The spin-multiplicity of the ¹⁴N nucleus was considered in the calculation of the partition function.
The dipole moment is from an ab initio calculation by
(2) K. A. Peterson, R. C. Woods, 1988, J. Chem. Phys. 89, 4929.