Correlation energies of simple bounded Coulomb lattices

The lattice structure of bounded Coulomb systems is explored using a simple zero-temperature slab model. For slabs above a certain size infinite-volume behavior (i.e., a bcc lattice) occurs. Below this size surface effects dominate and the lattice type depends on the size, usually taking on an fcc-like symmetry. This state is similar to the lattice observed in recent computer simulations. These results have implications for experiments now underway.