Cyanide radical

Term energies, transition frequencies, and A-values are based on the spectroscopic constants of Klisch et al. (1995) together with the dipole moment mu=1.45 Debye from Thomson & Dalby (1968). The data file includes all levels in v=0 up to N=20. Collision computations are from Lique et al (2010), and include the spin-rotation structure of CN but not the hyperfine structure. The data file gives He-impact rates scaled by 1.37 as though they are for H2. The Lique et al paper tabulates rate coefficients from 5 K to 300 K in steps of 5 K, but the number of temperatures has been reduced from from 60 to 12 in the data file. The data file also includes electron impact collisions: for the lowest transitions connecting N=0 these are from the close-coupling calculation of Allison & Dalgarno (1971), while the rates for the higher transitions are newly computed in the Born approximation.

The second datafile includes the hyperfine structure of CN, up to the N = 12 level at 295 cm-1 above ground. Collisions with ortho and para H2 are included, for temperatures from 5 to 100 K, as calculated by Kalugina & Lique (2015).

. Send comments to