Rotation–vibrational analysis for three states of NaH and NaD

Abstract

We have carried out a rotation–vibrational analysis for the X 1Σ+, A 1Σ+, and b 3Π states of NaH and NaD using accurate a b i n i t i o calculated potential curves. The calculated values of B e , α e , R e , ω e , and ω e x e (with known experimental values in parentheses) are NaH X 1Σ+ : B e = 4.748 (4.886) cm−1, α e = 0.126 (0.129) cm−1, R e = 3.625 (3.562) bohr, ω e = 1183.17 (1172.2) cm−1, and ω e x e = 21.23 (19.72) cm−1; NaD X 1Σ+ : B e = 2.475 (2.5575) cm−1, α e = 0.0474 (0.0520) cm−1, R e = 3.624 (3.565) bohr, ω e = 826.60 (826.10) cm−1 and ω e x e = 9.44 cm−1; NaH b 3Π : B e = 3.533 cm−1, α e = 0.853 cm−1, R e = 4.202 bohr, ω e = 419.39 cm−1 and ω e x e = 50.25 cm−1; NaD b 3Π: B e = 1.763 cm−1, α e = 0.265 cm−1, R e = 4.294 bohr, ω e = 311.95 cm−1 and ω e x e = 28.68 cm−1. The anomalous behavior of the B v ′s and ΔG v+1/2′s of the A 1Σ+ state is satisfactorily reproduced by these calculations: for NaH, B v (max ) = 1.9717 (1.941) cm−1 at v = 6 (6) and ΔG v+1/2 (max) = 381.37 (360.3) cm−1 at v = 9 (8); for NaD, B v (max) = 1.0274 (1.012) cm−1 at v = 8 (8) and ΔG v+1/2 (max) = 275.34 (260.22) cm−1 at v = 13 (12). The wavefunctions obtained were also used to calculate average electric dipole moments resulting in the following values (for the lowest rotation–vibrational states): for NaH, μ e (X 1Σ+) = 2.674 a.u., μ e (A 1Σ+) = 0.189 a.u., and μ e (b 3Π) = 0.158 a.u., for NaD, μ e (X 1Σ+) = 2.668 a.u., μ e (A 1Σ+) = 0.178 a.u., and μ e (b 3Π) = 0.163 a.u.