Multireference Møller–Plesset perturbation theory results on levels and transition rates in Al-like ions of iron group elements

Abstract

Ground configuration and low-lying levels of Al-like ions contribute to a variety of laboratory and solar spectra, but the available information in databases are neither complete nor necessarily correct. We have performed multireference Møller–Plesset perturbation theory calculations that approach spectroscopic accuracy in order to check the information that databases hold on the 40 lowest levels of Al-like ions of iron group elements (K through Ge), and to provide input for the interpretation of concurrent experiments. Our results indicate problems of the database holdings on the levels of the lowest quartet levels in the lighter elements of the range studied. The results of our calculations of the decay rates of five long-lived levels (3s23p 2Po3/2, 3s3p2 4PoJ and 3s3p3d 4Fo9/2) are compared with lifetime data from beam-foil, electron beam ion trap and heavy-ion storage ring experiments.