Energy levels, transition frequencies and Einstein A coefficients were taken from JPL for pure rotational lines. Vibration-rotation transition frequencies from Goddon et al. 1991. A-values computed from the transition dipole moments and fit to the Herman-Wallis factors of Pine et al. 1985. The values are similar (but not identical) to the values in HITRAN 2004.

Collisional rate coefficients with He are from Reese et al (2005), scaled by a factor 1.354 to represent collisions with H₂. Electron impact rates were calculated in the Coulomb-Born approximation.

• References
  Goddon, D. et al. 1991, J. Mol. Spec. 147, 392
  Pine, Fried, Elkins 1985, J. Mol. Spec. 109, 30
  Reese, C., Stoecklin, T., Voronin, A., Rayez, J.C. 2005, A&A 430, 1139