An Iso-Ionic Study of Excited Configurations in Singly Ionized Iron-Group Elements

A survey of recent analyses of Sc II, Ti II and Fe II and of other spectra of the singly-ionized iron-group elements demonstrates that the "horizontal" regularities first described by Catalan are valid for several kinds of excited configurations. From systematic parametric studies it is shown that the radial parameters have a smooth dependence on k for 3dk-14s4p, 3dk4d and 3dk4f configurations. From these results the position and level structure of unknown configurations can be predicted.