Journal of Advances in Applied Physics

JAAP
>
Volume 2, Number 2, May 2020

Pseudopotential for Many-Electron Atoms
DOI:

10.22606/jaap.2020.22002
**Author(s)**
Eric Ouma Jobunga

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

**Abstract**
Electron-electron correlation forms the basis of difficulties encountered in multi-electron
systems. 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 multi-electron problem,
two complementary parameter-free pseudopotentials for n-electron atoms are suggested in this
study. Using one of the pseudopotentials, near-exact values of the groundstate ionization energies of
helium, lithium, and berrylium atoms have been calculated. The other pseudopotential also proves
to be capable of yielding reasonable and reliable ionization energies within the non-relativistic
quantum mechanics framework.

**Keywords**
Electron-electron interaction, electron correlation, pseudopotential, multipole expansion.

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