THE NA2 41-SIGMA-G+ APPROXIMATELY 23-PI-G APPROXIMATELY 13-DELTA-G TRIPLE PERTURBATION - DEPERTURBATION OF THE (V-SIGMA, V-PI, V-DELTA = (6, 2, 7) AND (7, 3, 8) INTERACTIONS

Two examples of the 41Σg+ ∼ 23Πg ∼ 13Δg triple perturbation were observed by cw dye laser optical-optical double resonance spectroscopy via the A1Σu+ v′ = 5 intermediate state. The (vΣ, vΠ, vΔ) = (6, 2, 7) and (7, 3, 8) perturbation complexes were deperturbed, yielding the following molecular constants: T2 (23Πg) = 29027.102 (10) cm-1, ΔG 5 2 (23Πg) = 92.206 (10) cm-1, A (23Πg) = 4.06 (1) cm-1, B2 (23Πg) = 0.073740 (16) cm-1, T7 (13Δg) = 28979.385 (15) cm-1, ΔG 15 2 (13Δg) = 122.450 (25) cm-1, B7 (13Δg) = 0.117243 (20) cm-1, T6 (41∑+g) = 29010.357 (31) cm-1, ΔG 13 2(41∑+g) = 101.096 (44) cm-1, B6 (41∑+g) = 0.087626 (19)cm-1 and perturbation parameters: ζ(41∑+g ∼ 23Πg 〈 υ∑ | υπ〉 = 1.459 (16) cm- 1 at Rc = 4.64 A ̊:, α(23∑+g ∼ 13Πg 〈 υπ | υδ〉 = 0.16 (7) cm- 1 at Rc = 4.12 A ̊:, β(2(3Πg ∼ 13 Δg) lang;υπ | B (R) | υ δ〉 = 0.648 (20) A ̊:. In addition, the hyperfine structure of the 23Πgv = 2 level was sampled for all three Ω-components and many J-values. The hyperfine structure of the case aβ23Πg state is very similar to that in the b3Πu state and, like all singly excited triplet states of Na2, is dominated by the Fermi contact contribution from the singly occupied σg(3s) valence orbital. © 1991.