Theoretical level structure and decay dynamics of nickel-like ions: Searchfor laser lines in the soft X-ray domain

Multiconfiguration Dirac-Fockwave functions have been applied to study the level structure and transition probabilities of high-Z nickel-like ions in the range 74 less than or equal to Z less than or equal to 84. Several leve l crossings are found which strongly influence the decay dynamics of the ex cited ions and explain why some of these lines cannot (so easily) be observ ed for all elements along the isoelectronic sequence. For two selected ions , the role of configuration interactions and relaxation is explored by larg e-scale expansions.