Rotational line strengths for the cyanide B 2Σ - X 2Σ + (5,4) band

Rotational line strengths, computed from eigenvectors of Hund’s case (a) matrix representations of the upper and lower Hamiltonians using Wigner-Witmer basis functions, show a larger than expected influence from the well-known perturbation in the (5,4) band. Comparisons with National Solar Observatory experimental Fourier transform spectroscopy data reveal nice agreement of measured and predicted spectra. Keywords: Diatomic Spectroscopy; Rotational line strengths; H？nl-London factors; Cyanide spectra violet band perturbations