Ab initio calculation of fine structure inversion in the 3d10nf 2F3 levels of Kr7+

Recent measurements of the 3d10nf 2FJ (n=4,5,6,7) levels in Kr7+ show a fine structure inversion however previous experimental results predict that the 3d105f 2FJ levels are normal. Single configurational Dirac-Fock calculations predict that the levels are inverted but the effects are so small that configuration interaction could have a significant effect. To investigate this anomaly fully, multiconfigurational Dirac-Fock calculations including the most important core-excitation effects have been performed. Dirac-Fock calculations may predict fine structure inversion because the use of different radial wavefunctions for electrons with different j values effectively includes the major core polarisation effects which are known to induce fine structure inversion. To investigate this hypothesis, Hartree-Fock calculations including core polarisation potentials are being performed and the results will be presented