Theory of Quadrupole Polarizability and Antishielding of Nuclear Quadrupole Moments of Many-Electron Ions

Important corrections are proposed to earlier procedures for the calculation of quadrupole polarizabilities and antishielding factors of ions. A generalized formulation of the second-order perturbation theory for many-electron atoms and ions by Dalgarno is applied to ${\mathrm{K}}^{+}$ and ${\mathrm{Cl}}^{-}$ ions leading to increases of about 30 and 11%, respectively, over results of earlier variational calculations of the antishielding factors for these ions.