Energy levels, transition frequencies and Einstein A coefficients were taken from JPL. The collisional rates are taken from Danby et al. (1988) and were calculated for temperatures in the range from 15 to 300 K including energy levels up to about 420 cm^-1 for collisions with para-H₂. At present no extrapolated rate coefficients are made available.

• References
  Danby, G., Flower, D.R., Valiron, P., Schilke, P., Walmsley, C.M. 1988, MNRAS, 235, 229