Multielectron collection

A hydrogen atom or a helium cation contains Just one electron, but nearly all other atoms and ions contain collections of electrons. In a multielectron atom, each electron affects the properties of all the other electrons. These electron-electron interactions make the orbital energies of eveiy element unique. 

But also the gs deviates from the uncorrelated limits, with f, 0, in Fig. 11, panel b), even if, quite predictably, deviations are much smaller than for excited states. Finite near the discontinuous neutral-zwitterionic crossover show that the gs cannot be described as the product of local molecular states and therefore does not coincide with the mf or excitonic vacuum state the very same gs is collective in nature and 1-droplet states contribute to the gs. This is the key to understand multielectron transfer wave functions with 1-droplet character have, in C-clusters, very large permanent dipole moments, so that their finite amplitude in the gs is the origin of sizeable transition dipole moments towards states characterized by a high 1-droplet character. 

In the next fourth order, there appear diagrams, whose contribution into the ImA accounts for the core polarization effects. This contribution describes collective effects, and it is dependent upon the electromagnetic potential gauge (the gauge non-invariant contribution). Let us examine the multielectron atom with... 

---