CONTRIBUTIONS TO THE ELECTRON-AFFINITY OF CALCIUM AND SCANDIUM

Theoretical predictions of the electron affinity of Ca vary from 0 to 130 meV. Not all calculation, have included the same effects. In this paper, the different approaches are reviewed, the effect of assumptions estimated whenever possible, and some new ab initio results reported that estimate the effect of core polarization on electron affinity for both Ca and Sc. For the latter our predicted electron affinity is in good agreement with the experimental value for the lowest 4s(2)3d4p 1D state and underestimates the electron affinity for 4s(2)3d4p 3D, where the calculation of outer correlation is more demanding and the core-polarization effect is small.