Spectrum and Structure of the He2 Molecule. IV. Characterization of the Singlet and Triplet States Associated with the UAO's 3dσ, 3dπ, and 3dδ

Abstract

The electronic transitions 3dσf³Σ_u⁺, 3dπf³Π_u, 3dδf³Δ_u→3pσc³Σ_g⁺ of He₂ are described and term values presented for a number of vibrational levels for the 10 components of the singlet and triplet 3d complex. A detailed discussion of the methods of determination of reliable molecular constants in the presence of l uncoupling is presented, and the results applied to the 3d complexes of He₂. The following molecular constants (cm⁻¹), which have been corrected for l‐uncoupling effects, are reported: $$\begin{array}{cccccc}\mathrm{State}& {\omega }_e& {\mathrm{x\omega }}_e& B_e& {\alpha }_e& r_e\mathrm{(\AA )}\\ & & & & & \\ f^3{\Delta }_u& \text{1706.82}& \text{35.10}& \text{7.230}& \text{0.229}& {\text{1.079}}_1\\ f^3{\Pi }_u& \text{1661.48}& \text{44.79}& \text{7.136}& \text{0.233}& {\text{1.086}}_2\\ f^3{\Sigma }_u^{+}& \text{1635.77}& \text{44.41}& \text{7.071}& \text{0.246}& {\text{1.091}}_2\\ F^1{\Delta }_u& \text{1706.59}& {\text{35.06}}_5& \text{7.230}& \text{0.225}& {\text{1.079}}_1\\ F^1{\Pi }_u& \text{1670.57}& \text{40.03}& \text{7.156}& \text{0.235}& {\text{1.084}}_7\\ F^1{\Sigma }_u^{+}& & & \text{7.098}& \text{0.246}& {\text{1.089}}_1.\end{array}$$