A semiempirical analysis of perturbations in the triplet 3s, 3d complex of molecular hydrogen: The radiative lifetimes for rovibronic levels of the h 3Σ g + , g 3Σ g + , i 3Π g + , and j 3Δ g + states of H2

Abstract

The dependences of the radiative lifetimes τnvN for rovibronic levels of the h 3Σ g + , g 3Σ g + , i 3Π g + , and j 3Δ g + states on the vibrational, v, and rotational, N, quantum numbers (v=0–3 and N=1–6) of H2 have been derived for the first time. We calculated the absolute values of τnvN in terms of a nonadiabatic model that incorporates the interaction between the (3sσ)3Σ g + , (3dσ)3Σ g + , (3dπ)3Π g + , and (3dδ)3Δ g + states by using our semiempirical expansion coefficients for the wave functions in the Born-Oppenheimer basis and the dipole moments for electronic transitions to the (2pπ)3Σ u + and (2pπ)3Πu states. We analyze the perturbations of the radiative lifetimes for rovibronic levels of the h 3Σ g + , g 3Σ g + , i 3Π g + , and j 3Δ g + states in the triplet 3s, 3d complex of H2. Considerable differences (reaching a factor of 5 for h 3Σ g + and a factor of 2 for i 3Π g + were found between the non-adiabatic and adiabatic radiative lifetimes of rovibronic levels. These differences can be explained both by a significant effect of the (3sσ)3Σ g + state in the i 3Π g + perturbation and by a considerable difference (reaching an order of magnitude) between the adiabatic values of τnvN for (3sσ)3Σ g + and (3dπ)3Π g + . The differences between the nonadiabatic and adiabatic lifetimes for rovibronic levels of the g 3Σ g + and j 3Δ g + states are much smaller (no more than 11%).