The Accommodation of Excess Charge in Binary Particle Lattices: A Many-Body Electrostatic Study

Many binary particle lattices are fabricated from charged particles on the assumption that the resultant structure is overall charge neutral. Results presented here from calculations on nine separate particle lattice types show that when both Coulomb and many-body multipole electrostatic interactions are taken into account, a lattice can actually gain stability by accommodating a small excess charge, either positive or negative. This effect arises from an increase in stability due to charge-induced multipole interactions, which serve to counteract destabilizing interactions that arise from repulsive Coulomb forces. It is shown that most of the lattice types considered could accommodate over 20% excess charge before becoming completely destabilized.