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arXiv · 0908.1362

Phase diagram of hard colloidal platelets: a theoretical account

H. H. Wensink·H. N. W. Lekkerkerker
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Abstract

We construct the complete liquid crystal phase diagram of hard plate-like cylinders for variable aspect ratio using Onsager's second virial theory with the Parsons-Lee decoupling approximation to account for higher-body interactions in the isotropic and nematic fluid phases. The stability of the solid (columnar) state at high packing fraction is included by invoking a simple equation of state based on a Lennard-Jones-Devonshire (LJD) cell model which has proven to be quantitatively reliable over a large range of packing fractions. By employing an asymptotic analysis based on the Gaussian approximation we are able to show that the nematic-columnar transition is universal and independent of particle shape. The predicted phase diagram is in qualitative agreement with simulation results.

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H. H. Wensink, H. N. W. Lekkerkerker. 2009-08-10. Phase diagram of hard colloidal platelets: a theoretical account. https://doi.org/10.1080/00268970903160605

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