Cyanide radical
LAMDA | RADEX on-line

Term energies, transition frequencies, and A-values are based on the spectroscopic constants of Klisch et al. (1995, A&A, 304, L5) together with the dipole moment mu=1.45 Debye from Thomson & Dalby (1968, Can. J. Phys. 46, 2815). The data file includes all levels in v=0 up to N=20. Collision computations are from Lique et al (2010, J. Chem. Phys., 132, 024303) 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, A&A 13, 331) while the rates for the higher transitions are newly computed in the Born approximation.

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