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Re-entrant Melting in Polydisperse Hard Spheres

Paul Bartlett·Patrick B. Warren
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Abstract

The effect of polydispersity on the freezing transition of hard spheres is examined within a moment description. At low polydispersities a single fluid-to-crystal transition is recovered. With increasing polydispersity we find a density above which the crystal melts back into an amorphous phase. The range of densities over which the crystalline phase is stable shrinks with increasing polydispersity until, at a certain level of polydispersity, the crystal disappears completely from the equilibrium phase diagram. The two transitions converge to a single point which we identify as the polydisperse analogue of a point of equal concentration. At this point, the freezing transition is continuous in a thermodynamic sense.

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Paul Bartlett, Patrick B. Warren. 1999-02-02. Re-entrant Melting in Polydisperse Hard Spheres. https://arxiv.org/abs/cond-mat/9902029

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