Breit and QED effects on the 3d9 D3/2 2 →2D5/2 transition energy in Co-like ions
The multiconfiguration Dirac-Hartree-Fock theory is used to calculate the 3d9D3/22→2D5/2 transition energy for Co-like ions with Z=28-100. We investigate how electron correlation, frequency-independent and -dependent Breit interactions, as well as QED corrections vary along the sequence. The well-understood frequency-independent Breit contribution has the largest contribution for all ions. Among t