(667c) Equations of State for Hard Polyhedra

The role of shape in entropy-driven self-assembly has recently been highlighted in computer simulations of hard anisotropic particles. A rich diversity of crystal and other solid-like phases has been demonstrated in particular for hard polyhedra [1-5]. Hard polyhedra and other simple shapes can be good models for nano crystalline colloids when interactions are dominated by geometry. Though advancements in the synthesis of such nanoparticles[7] are expanding our ability to create novel fluids and structured hierarchical materials, our understanding of the thermodynamics of anisotropic particles is still limited. Here we present equations of state for systems of hard polyhedra spanning the low-density fluid to high-density solid states, obtained numerically from equilibrium Monte Carlo simulations. We compare the results to various forms of equations of state from free volume and scaled particle theory.  We discuss trends in the behavior for different shapes, and show some general features common to all systems.

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