(303j) Assessing the Thermodynamic Stability of Ordered Phases of Hard Facetted Building Blocks

Anisotropic colloidal building blocks are capable of assembling into a wide array of complicated ordered structures. Such ‘exotic’ assemblies have been observed in both experimental and computational studies of self-assembly. It is even possible that multiple crystallization pathways are available to a system, some inevitably leading to metastable structures that only form due to kinetic frustration. Determining the relative thermodynamic stabilities of such competing structures is, however, not always trivial. In this work, we discuss computational procedures for estimating the free energies of complex ordered structures formed by anisotropic facetted building blocks. The presented approach is independent of the particular shape of the building block and only depends on the type of the crystal of interest. As case studies, we consider several crystalline phases assembled by hard Platonic and Archimedean solids [1-4]. In particular, we assess the thermodynamic stability of several novel packings that we have discovered [4] in the hard dodecahedron system.

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[3] Haji-Akbari et al. Phys. Rev. Lett. 107: 215702 (2011).

[4] Damasceno et al. Science 337: 453 (2012).