Fine structure of the 1s2s2p4P degrees and 1s2p24P terms of the lithium isoelectronic sequence and wavelengths of transitions between them

Recent MCDF (-OL) calculations by Cheng et al. (1978) of the fine structure of the 1s2s2p 4 P 0 and 1s2p 2 4 P terms in lithium-like ions and of the wavelengths of transitions between them show indifferent agreement with available experimental measurements. The authors have repeated the calculations using the same set of CSF but employing the MCDF-EAL method; fine structures for C IV, N V, O VI and Mg X are now predicted to lie within experimental error limits for the most part, and wavelengths are correct to about one part in 10 3 . Some reasons for this striking improvement are discussed.