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arXiv · 1005.4571

Glassy dynamics, spinodal fluctuations, and the kinetic limit of hard-rod nucleation

Ran Ni·Simone Belli·Rene van Roij·Marjolein Dijkstra
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Abstract

Using simulations we identify three dynamic regimes in supersaturated isotropic fluid states of short hard rods: (i) for moderate supersaturations we observe nucleation of multi-layered crystalline clusters; (ii) at higher supersaturation, we find nucleation of small crystallites which arrange into long-lived locally favored structures that get kinetically arrested, while (iii) at even higher supersaturation the dynamic arrest is due to the conventional cage-trapping glass transition. For longer rods we find that the formation of the (stable) smectic phase out of a supersaturated isotropic state is strongly suppressed by an isotropic-nematic spinodal instability that causes huge spinodal-like orientation fluctuations with nematic clusters diverging in size. Our results show that glassy dynamics and spinodal instabilities set kinetic limits to nucleation in a highly supersaturated hard-rod fluids.

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Ran Ni, Simone Belli, Rene van Roij, Marjolein Dijkstra. 2010-07-15. Glassy dynamics, spinodal fluctuations, and the kinetic limit of hard-rod nucleation. https://doi.org/10.1103/physrevlett.105.088302

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