Spectrum and structure of the He2 molecule . Characterization of the singlet and triplet states associated with the UAO's 4s, 4dσ, 4dπ, and 4dδ</SBT>
The emission spectrum of the He 2 molecule has been rephotographed in the ∼4000-∼5700 Å region and the 4d( 3Σu+, 3Πu, 3∆u) → 2pπ 3Πg, 4d( 1Σu+, 1Πu, 1∆u) → 2pπ 1Πg, 4s 3Σu+ → 2pπ 3Πg and 4s 1Σu+ → 2pπ 1Πg transitions analyzed. The 4 dδj3∆ u, 4 dπj3Π u, 4dσj 3Σu+ and 4sh 3Σu+ states have been characterized through v = 2 and the 4 dδJ1∆ u, 4 dπJ1Π u, 4dσJ 1Σu+, and 4sH 1Σu+ states for v = 0. The term levels for these perturbed and l-uncoupled states have been confirmed (a) by analyses of bands with common levels from ∆ v = 0, ±1 sequences and (b) by analyses of the transitions between the above states from 4 d and 4 s and the c 3Σg+ and C 1Σg+ states associated with 3 pσ. Molecular constants are reported which have been partially corrected for the effects of l-uncoupling and the homogeneous perturbations between the state pairs J, H and j, h.