  We report exact multielectronic ground-states dependent on electron
concentration for quantum mechanical two-dimensional disordered two-band type
many body models in the presence of disordered hoppings and disordered
repulsive finite Hubbard interactions, in fixed lattice topology considered
provided by Bravais lattices. The obtained ground-states loose their
eigenfunction character for independent electron approximation, perturbatively
are not connected to the non-interacting but disordered case, and describe a
localization-delocalization transition driven by the electron concentration,
being highly degenerated and paramagnetic.
