Ground State Energies of Interacting Electrons from Projected Densities   of Transitions
  For interacting electrons in solids, Heisenberg's equation is used to calculate the distribution in energy of transitions induced by adding an electron to an atomic-like spin orbital. This is the projected density of transitions which includes transitions between grounds states, as well as between other states differing by one electron. The energy of a ground state is then calculated as the sum of the least energies of transitions starting with the ground state of no electrons and adding one electron with each transition. This method is applied to the construction of ground states for a simple model of the hydrogen molecule, and to interaction effects on the relative cohesion of HCP and FCC structures of transition metals. 
Roger Haydock
cond-mat.str-el