Influence of electronic relaxation on core and valence excited states of alkaline-earth atoms

The dependence on the hole quantum numbers of single-particle excited states of the alkaline-earth atoms Be, Mg, and Ca is studied within the Hartree-Fock frozen-core method. For a given orbital state of the outer electron, we find that the term values of all core excitations are nearly the same but they differ from that of the valence excitation. The similarity of the core Rydberg series is explained in terms of the electron-density relaxation. The first term of a Rydberg series is anomalous when the excited electron penetrates appreciably into the atomic core. Our findings are compatible with all available experimental data. The latter, however, are not accurate enough to confirm the predicted similarity among the core Rydberg series.