New Horizons in Mathematical Physics

NHMP
>
Volume 4, Number 2, June 2020

Partitioning of the Electron-Electron Interaction
DOI:

10.22606/nhmp.2020.42001
**Author(s)**
Eric Ouma Jobunga

**Affiliation(s)**
Department of Mathematics and Physics, Technical University of Mombasa, P. O. Box 90420-80100, Mombasa, Kenya

**Abstract**
Electron-electron correlation forms the basis of difficulties encountered in many-body
problems. Accurate treatment of the correlation problem is likely to unravel some nice physical
properties of matter embedded in this correlation. In an effort to tackle this many-body problem,
a classical partition function for the electron-electron correlation between two interacting states is
proposed in this study. Using this partition function, a model potential for a two-electron system is
derived. The model potential can accurately reproduce the singlet states of a singly excited neutral
helium atom with one of its electrons frozen in the 1s orbital.

**Keywords**
electron-electron interaction, correlation energy, helium, partitioning, multipole expansion.

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