Contribution of three-body potentials to the binding energy of heavy atoms
The conversion of quantum electrodynamics to a configuration-space Hamiltonian formalism introduces three-electron potentials of relativistic origin. For heavy atoms, it is found that the contribution of these potentials to the inner-shell binding energy is no more than 0.21 eV. This is too small to explain the discrepancy between current theory and experiment. The uniqueness of the potentials obtained in the configuration-space Hamiltonian is also discussed.