Plastic crystal phases of hard dumbbells and hard spherocylinders

Abstract

We compare the solid-fluid phase diagrams calculated from computer simulations of hard dumbbells and hard spherocylinders in the region of anisotropy where a plastic crystal phase is stable for both systems. When appropriate reduced units are used for the pressure and densities, the coexistence properties for these models are very similar. The existing evidence suggests that for both models the density change on freezing of the fluid into the plastic crystal phase becomes very small as the limit of stability of the plastic crystal phase is reached, but the transition remains first order.