Spark spectrum of mercury, Hg II

Abstract

The one-electron doublet spectrum of Hg II was analysed very thoroughly by Paschen after a few of its most stable terms had been identified by Carroll. Minor features were added to the knowledge of its structure by Rasmussen and by Naudé. Paschen also identified the low inverted 2 D term and seven higher terms and Naudé a number of additional ones of the complex structure of Hg II that originates in many-electron configurations of the Hg + ion. Naudé assigned L and S characteristics to most of his and Paschen’s complex terms. The authors have recently been carrying out an investigation of the structures, that originate in complex configurations, of the iso-electronic Au I, Hg II and T1 III spectra. The analysis of Au I made some time ago by two of us has been extended and the interpretation of its complex structure modified somewhat in view of the fact that the couplings of quantum vectors of electrons of the neutral gold atom were found to be more nearly of the jj type than had been supposed previously. A similar conclusion about electron couplings in Hg + and Tl ++ ions has been reached by us in our investigations of Hg II and T1 III spectra. A paper on the structure of Au I has just been sent to press. The analysis of T1 III is not yet completed, but it is hoped that results can be published at an early date.