A study of 5p excitation in atomic barium. II. A fully relativistic analysis of 5p excitation in atomic barium

Abstract

A fully relativistic ab-initio multiconfiguration Dirac-Fock (m.D.-F.) procedure has been used to identify six prominent peaks in the 5p electron-impact ionization spectrum of Bai and thereby also suggest assignments for each series limit in the 5p-photoabsorption (synchrotron radiation) spectrum of Ba I. Comparison between single configuration m.D.-F. and non-relativistic H.—F. intermediate coupling calculations show differences in the predicted ordering of levels; triple manifold m.D.-F. calculations show the interaction between configurations 5p 5 6s 2 , 5p 5 5d 6s and 5p 5 5d 2 of Ba II to be responsible for the prominence of supernumerary excitations in each experiment.