Abstract
A method is described whereby it is possible to make accurate empirical estimates of ionization potentials that are missing in Moore's "atomic energy levels," and so obtain empirical total atomic binding energies BZ with estimated uncertainties less than 0.005%, for all Z<~18. These BZ values are used to compute values of BZZ, with quite small a signed uncertainties (∼0.15% for Z>~12). The relativistic Dirac-Hartree-Fock calculations of Mann reproduce these empirical values to within amounts a few times the uncertainties.