  Electron-electron correlation forms the basis of difficulties encountered in
many-body physics. Accurate treatment of the correlation problem is likely to
unravel some nice physical properties of matter embedded in the correlation. In
an effort to tackle the many-body problem, an empirically determined
symmetry-dependent partition fraction for the electron-electron interaction
energy between two interacting states of helium atom is suggested in this
study. Using the partition fraction and the lowest-order approximation of the
multipole series expansion of the electron-electron interaction, a simple
parameter-free pseudopotential for a two-electron system is derived. The
groundstate, singly and doubly excited state non-relativistic energies
generated by the pseudopotential are in reasonable agreement with literature
values.
