Core and valence electrons in atoms and ions: configuration interaction calculations

Summary The partitioning of ground-state atoms or ions into inner spherical cores with radius _b and outer valence regions extending from _b to infinity is explored with the help of the expression for the valence-region energy (where T^v and V^v are, respectively, the kinetic and potential energies of the valence electrons N^v found beyond the boundary surface defined by _b) using also the appropriate expression for E^ion, the energy of the ion left behind after removal of the valence electrons. E^v and E^ion are meaningful only for discrete numbers, N^c, of electrons assigned to the core, namely, when the exchange integrals, K^cv, between N^c and N^v total (or at least closely approach) 0, i.e., for N^c = 2 e or N^c = 2 and 10 e for the first- or second-row elements, respectively.Part of the projected Ph.D. dissertation of N. D.