Extended Analysis of the Emission Spectrum of Neutral Ytterbium (Yb I)

In order to prepare a theoretical analysis of Rydberg series 4 f 14 6 snl the classification of the spectrum of neutral ytterbium has been extended with the help of new observations in the infrared and measurements of Zeeman effect in the visible and near ultraviolet. 176 lines are classified by 70 new levels. The configurations 4 f 13 6 s 2 6 p and 4 f 14 6 p 2 are now complete and the lowest levels of 4 f 13 5 d 2 6 s and 4 f 14 5 d 6 p have been recognized, as well as new low members of the Rydberg series. In both parities a parametric study of the configurations taking into account mixing effects has led us to revise and to extend the earlier labeling. All the perturbers of the 4 f 14 6 snl series have been found or predicted. A reinterpretation of the autoionizing levels observed by Parr and Elder is also needed.