LETTER TO THE EDITOR: Trends in valence autoionizing Rydbergs for ? semifilled-shell ground and excited atoms and ions: ? and Re

New regularities are reported for valence-shell autoionizing Rydbergs decaying to a continuous spectrum of the valence subshell of free metal atoms and ions with semifilled subshells: , , and . We predict an extreme narrowing for the autoionizing Rydbergs in the atoms and ions with a ground-state valence-shell configuration. In contrast, incomparably broader Rydbergs occur in both atoms and ions with a ground configuration , or in metastable atoms and ions whose electron configuration is . We also predict a drastic difference between the Rydberg profiles in partial and photoionization cross sections of the atoms and ions with a closed valence subshell (arrows and show the two possible spin orientations for the ejected photoelectrons). The regularities disappear for atoms and ions with other than an semifilled subshell. The research is performed within both the `spin-polarized' Hartree - Fock approach and the `spin-polarized' random-phase approximation with exchange.