Perturbation between Rydberg states

Electrostatic Perturbations between Rydberg States Converging to Different States of the Ion... 

Korona T, Jeziorski B, Moszynski R, Diercksen GHF (1999) Degenerate symmetry-adapted perturbation theory of weak interactions between closed- and open-shell monomers application to Rydberg states of helium hydride. Theor Chem Acc 101 282-291... 

Figure 3.10 Perturbations between the 6pw and llj>7r 1n Rydberg states of H2. Two Rydberg series converging to different vibrational levels of the X2E state interact via nonzero Av — 1 vibrational matrix elements of the d/dR operator.

Electrostatic Perturbations Between Valence and Rydberg States.312... 

Let us first consider the rotational interaction between discrete Rydberg states. For example, the and 1E+ levels of an up-complex of H2 are mixed by the 1-uncoupling term in HROT. Since AE == 0, the selection rule AO = 1 implies that AA = 1. The 2 x 2 1II 1E+ perturbation secular determinant for the Jth rotational levels, expressed in the case (a) basis, is, for l = 1,... 

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