Spin-orbit perturbations among the D 1Δ(v = 10), d 3Δ(v= 14), a3Π(v = 18), and a′ 3Σ+ (v = 19) levels of carbon monoxide have been observed in the two-photon laser excitation spectrum of the D 1Δ-X 1Σ+ (10-0) band. Spectra have been analyzed using a weighted nonlinear least-squares-fitting method. Detailed assignments and wave numbers are presented for the D-X ( 10-0), a-X (18-0), and d-X (14-0) bands. Molecular constants and perturbation parameters have been determined, and mixing coefficients have been calculated. Electronic perturbation parameters associated with the D 1Δ ∼ a 3Π spin-orbit interaction and the d 3Δ ∼ D 1Δ isoconfigurational interaction are obtained for the first time. The latter parameter could be determined because of an unusual multiple crossing among the a, d, and D states. The v = 18 level is the highest vibrational level of the a 3Π state ever observed.
ASJC Scopus subject areas
- Physics and Astronomy(all)
- Physical and Theoretical Chemistry