(446f) Effect of Building Block Geometry On the Stability of Ordered Phases of Hard Tetrahedra

For many years, hard spheres were extensively studied as simple models of atoms in liquids and solids. At larger length scales, hard-core interactions have been shown to approximate short-range repulsions achievable in colloidal systems. Qualitative phase diagrams of such systems can therefore be predicted via computer simulations of hard particles. In recent years, an increasing interest has developed for non-spherical hard particle systems as synthesis of anisotropic nano- and colloidal particles of different shapes have become possible due to breakthroughs in synthesis and fabrication techniques. These anisotropic building blocks are of practical interest due to their potential mechanical, electrical or optical properties. Hard regular tetrahedra are one of the simplest anisotropic particles extensively studied in recent years [1-4]; they have been shown to form quasicrystalline and crystalline phases. Here we present new results of Monte Carlo simulations of related hard particle geometries to understand how the thermodynamic stabilities of various ordered structures formed by hard tetrahedra are affected when the geometry and anisotropy of the building block is altered.

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4. A. Haji-Akbari, M. Engel, S. C. Glotzer, Phase diagram of hard tetrahedra. preprint.