Shielding Efficiencies Determined from Atomic Spectroscopy for Use in Semi Empirical SCF-MO Calculations

In an empirical study of 2200 atomic configurations from H up to Kr (Z = 36) it is shown that the atomic energies can be calculated using Slater's method. The condition is that the shielding efficiencies have the form α - β/ξμ where ξμ is the orbital exponent of the shielded electron. The average error is then 0.1 eV.