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abstract: 'A relativistic effective charge model has been developed for computation of observable characteristics of multi-electron atoms and ions. A complete and orthogonal Dirac hydrogen basis set, depending on one parameter — effective nuclear charge $Z^{*}$ — identical for all single-electron wave functions of a given atom or ion, is employed for the construction of the secondary-quantized representation. The effective charge is uniquely determined by the charge of the nucleus and a set of electron occupation numbers for a given state. We thoroughly study the accuracy of the leading-order approximation for the total binding energy and demonstrate that it is independent of the number of electrons of a multi-electron atom. In addition, it is shown that the fully analytical leading-order approximation is especially suited for the description of highly charged ions since our wave functions are almost coincident with the Dirac-Hartree-Fock ones for the complete spectrum. Finally, we envision that our effective charge model is more accurate and thus can replace the Thomas-Fermi-Dirac model for all applications where it is still utilized.'
author:
- 'K. Dzikowski'
- 'O. D. Skoromnik'
- 'I. D. Feranchuk'
- 'N. S. Oreshkina'
- 'C. H. Keitel'
bibliography:
- 'relativistic\_zeroth.bib'
title: 'Relativistic effective charge 