ELECTRON-AFFINITY IN DENSITY-FUNCTIONAL THEORY IN THE LOCAL-SPIN-DENSITY APPROXIMATION

Ionization potentials for most atoms are described accurately by total -energy differences calculated within density-functional theory (DFT) in the local-spin-density approximation (LSD). Electron affinities can not be obtained in the same way, because the long-range behavior of th e LSD potential is incorrect and negative ions are not bound. Were I s how how electron affinities can be accurately estimated taking advanta ge of the nearly quadratic dependence of the LSD energy on the occupat ion numbers around the neutral atomic configuration. The procedure yie lds electron affinities, for plain LSD atoms, in better agreement with experiments than other self-interaction corrected DFT-based results. [S1050-2947(98)03402-7].