Martin expression about the quantum defect of single-valence atoms is extended to many-valence atoms by identifying the weakest bound electron (WBE) under the weakest bound electron potential model (WBEPM) theory. Six Rydberg series energy levels of 2p6np2Po_(1/2) (n>3), 2p6np2Po_(3/2) (n>3), 2p6nd2D_(3/2) (n>3), 2p6nd2D_(5/2) (n>3), 2p6nf2Fo_(5/2) (n>4), and 2p6nf2Fo_(7/2) (n>4) for Ni XVIII are calculated by this method. The calculated results are in good agreement with the experimental results.
© 2007 Chinese Optics Letters
Chao Zhou, Liang Liang, and Ling Zhang, "Calculations of Rydberg energy levels for Ni XVIII using the weakest bound electron potential model theory," Chin. Opt. Lett. 5, 438-440 (2007)