  We consider the Schr\"odinger--Poisson--Newton equations for finite crystals
under periodic boundary conditions with one ion per cell of a lattice. The
electron field is described by the $N$-particle Schr\"odinger equation with
antisymmetric wave function.
  Our main results are i) the global dynamics with moving ions, and ii) the
orbital stability of periodic ground state under a novel Jellium and
Wiener-type conditions on the ion charge density. Under Jellium condition both
ionic and electronic charge densities of the ground state are uniform.
