Relativistic ionization energies of the helium-like ions

Abstract

The ionization energies of the helium-like ions with nuclear charge numbers Z (2 < Z < 100) are calculated within the framework of Relativistic Schrodinger Theory (RST). The corresponding energy-eigenvalue problem in the Coulomb field of a point-like fixed nucleus is worked out in detail and numerical solutions for the ground state 1s 2 1 S 0 are obtained. The relativistic energy functional for the isotropic bound states is studied in detail, and its value upon the constructed ground-state solutions yields the ionization energy for both cases where the electronic self-energy is either included or neglected. The combination of the RST two-particle self-energy with the one-particte Lamb shift of QED yields predictions for the ionization energies, which for the relativistic domain (high nuclear charge numbers) agree well with the experimental data.