Hartree atomic orbital shielding effects

The early calculations by Dickinson [168] of the diamagnetic shielding in atoms using Hartree or Hartree-Fock SCF atomic orbitals made it clear that the major contribution to is due to inner shell electrons and that the relative contribution of the outer electrons decreases markedly with atomic number Z. As a consequence of this are the values for atoms rather insensitive to the effective atomic... 

Even in cases where the SFR effects alone are negligible, their inclusion may be warranted to obtain a good description of SO effects. This is due to the fact that the all-electron SO operators probe the inner tails of the valence orbitals, and SFR effects on the position of the radial nodes of these orbitals are thus potentially important [114]. This is apparent in some of the conputational results obtained, e.g., fi-om a number of quasirelativistic all-electron Hartree-Fock studies of heavy-atom shieldings [82,116]. In contrast, in SO-ECP... 

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