An analysis of the exchange correlation effects in the isoelectronic series of the2S ground state of lithium in terms of the interelectronic distance

Abstract

The hole formalism has been used to elucidate exchange correlation effects in the2S state of the lithium isoelectronic series. This approach provides a very simple physical picture of the effects of electron correlation from the point of view of the reference electron. In particular the calculations demonstrate that the probability of finding any two electrons with the same spin is reduced at both small and large interelectronic distances with a concomitant increase of the probability of their being at intermediate distances. Also a general tendency for the radius of the Fermi hole to increase as a function of r1has been shown together with the existence of a non-zero limit. Finally the authors have found that the polarisation of the Fermi hole is spherically symmetric with respect to the nucleus and has very little dependence on the distance of the reference electron from the nucleus.