The Na2 41Σg+ ∼ 23Πg ∼ 13Δg triple perturbation: Deperturbation of the (vΣ, vΠ, vΔ) = (6, 2, 7) and (7, 3, 8) interactions

Abstract Two examples of the 4 1 Σ g + ∼ 2 3 Π g ∼ 1 3 Δ g triple perturbation were observed by cw dye laser optical-optical double resonance spectroscopy via the A 1 Σ u + v ′ = 5 intermediate state. The ( v Σ , v Π , v Δ ) = (6, 2, 7) and (7, 3, 8) perturbation complexes were deperturbed, yielding the following molecular constants: T 2 (2 3 Π g ) = 29027.102 (10) cm −1 , ΔG 5 2 (2 3 Π g ) = 92.206 (10) cm −1 , A (2 3 Π g ) = 4.06 (1) cm −1 , B 2 (2 3 Π g ) = 0.073740 (16) cm −1 , T 7 (1 3 Δ g ) = 28979.385 (15) cm −1 , ΔG 15 2 (1 3 Δ g ) = 122.450 (25) cm −1 , B 7 (1 3 Δ g ) = 0.117243 (20) cm −1 , T 6 (4 1 ∑ + g ) = 29010.357 (31) cm −1 , ΔG 13 2 (4 1 ∑ + g ) = 101.096 (44) cm −1 , B 6 (4 1 ∑ + g ) = 0.087626 (19)cm −1 and perturbation parameters: ζ(4 1 ∑ + g ∼ 2 3 Π g 〈 υ ∑ | υ π 〉 = 1.459 (16) cm − 1 at R c = 4.64 A : , α(2 3 ∑ + g ∼ 1 3 Π g 〈 υ π | υ δ 〉 = 0.16 (7) cm − 1 at R c = 4.12 A : , β(2( 3 Π g ∼ 1 3 Δ g ) lang;υ π | B (R) | υ δ〉 = 0.648 (20) A : In addition, the hyperfine structure of the 2 3 Π g v = 2 level was sampled for all three Ω-components and many J -values. The hyperfine structure of the case a β 2 3 Π g state is very similar to that in the b 3 Π u state and, like all singly excited triplet states of Na 2 , is dominated by the Fermi contact contribution from the singly occupied σ g (3 s ) valence orbital.