Electron Correlation Energies in the Neutral Iron Atom

Abstract

The many-body perturbation theory of Brueckner and Goldstone is used to calculate the electron correlation energy among the $n=3$ and $n=4$ electrons of FeI. The results is - 0.7155 a.u. Combined with a semiempirical estimate of correlations from the ${(1s)}^{2}{(2s)}^{2}{(2p)}^{6}$ core, the total correlation energy of FeI is - 1.165 a.u.