Relativistic study ofK-shell x-ray and Auger-electron energy shifts for additional atomic vacancies

The hydrogenic model of Burch et al. for calculating the energy shifts of the K x ray and Auger electrons for a vacancy in the L shell is extended to incorporate the effect of relativity. Numerical results are presented for 18 values of Z (from 10 to 95 in steps of 5). The computations are based on two different choices of the screening parameters. The effective nuclear charges (Zeff) determined by the method of O'Connell and Carroll yield numbers for the energy shifts close to the predictions of Hartree-Fock (HF) and Hartree-Fock-Slater (HFS) calculations. On the other hand, Zeff obtained from Slater's rule gives numbers which are considerably larger than the HF and HFS values. However, the choice of screening is crucial only for low-Z elements and relativity plays an increasingly dominant role as one goes to higher atomic numbers. It is found that the relativistic effect is more pronounced for a vacancy in the L₂ subshell.