Many-body perturbation-theory calculations of energy levels along the sodium isoelectronic sequence.

Abstract

Energies of 3s and 3p states of sodiumlike ions are calculated from Z=11 to Z=92 starting from a Dirac-Fock potential and including second- and third-order Coulomb correlation corrections, the lowest-order Breit interaction with retardation treated exactly, second- and third-order correlation corrections to the Breit interaction, and corrections for reduced mass and mass polarization. The calculated energies are compared to measured energies to determine the size of the omitted quantum electrodynamics corrections.