The Stark effect in the 6 snf Rydberg series of barium.

In the last paper on the polarizabilities in the 6 snf Rydberg series of barium results for the 6 snfF levels with n=13-40 are reported. The scalar and tensor polarizabilities are analyzed using existing data on the adjacent even-parity 6 snd D series as well as data on neighbouring 6 sng G and G series derived from the polarizabilities of the 6 snf F and F series. This results in information on the to a large extent unknown 6 sng G series and confirms the perturbation of this series in between n=15 and 16 by the doubly excited 5d7dG level. A tentative two-channel quantum-defect analysis is presented. In conclusion the results on the 6 sng configuration deduced from the study of the quadratic Stark effect in the 6 snf configuration are summarized. [ABSTRACT FROM AUTHOR]