  We extend a previously studied lattice model of particles with infinite
repulsions to the case of finite energy interactions. The phase diagram is
studied using grand canonical Monte Carlo simulation. Simulations of dynamical
phenomena are made using the canonical ensemble. We find interesting
order-disorder transitions in the equilibrium phase diagram and identify
several anomalous regimes of diffusivity. These phenomena may be relevant to
the case of strong orientational bonding near freezing.
