Zur Hyperfeinstruktur des Eu-II

By means of a Fabry-Pérot-interferometer the hyperfine structure of 10 lines of the Eu-II-spectrum was analysed and from the results splitting factors and isotope shifts were calculated. When evaluating the magnetic momentμ, of Eu_{1 1} it was found that the two ground states (a⁹S ₄ ⁰ and a⁷S ₃ ⁰ ) of the Eu-II yield two distinctly different values for μ. This discrepancy can be removed assuming that a different electronic splitting factor (a_{6 s}) has to be attributed to the 6s-electron in each of these two states.