On the reliability of semi-empirical pseudopotentials: simulation of Hartree-Fock and Dirac-Fock results

Abstract
Semi-empirical pseudopotentials can be modified in a simple way so as to reproduce frozen-core Hartree-Fock or Dirac-Fock results, respectively. The influence of relativistic effects is quantitatively discussed (i) for (rn) expectation values and dipole polarisabilities of group IA and IB atoms, and (ii) for the bond lengths of K2+ and Cu2.