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arXiv · 2009.08879

Defying the Gibbs Phase Rule: Evidence for an Entropy-Driven Quintuple Point in Colloid-Polymer Mixtures

V. F. D. Peters·M. Vis·Á. González García·H. H. Wensink·R. Tuinier
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Abstract

Using a minimal algebraic model for the thermodynamics of binary rod--polymer mixtures, we provide evidence for a quintuple phase equilibrium; an observation that seems to be at odds with the Gibbs phase rule for two-component systems. Our model is based on equations of state for the relevant liquid crystal phases that are in quantitative agreement with computer simulations. We argue that the appearance of a quintuple equilibrium, involving an isotropic fluid, a nematic and smectic liquid crystal, and two solid phases can be reconciled with a generalized Gibbs phase rule in which the two intrinsic length scales of the athermal colloid--polymer mixture act as additional field variables.

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V. F. D. Peters, M. Vis, Á. González García, H. H. Wensink, R. Tuinier. 2020-09-18. Defying the Gibbs Phase Rule: Evidence for an Entropy-Driven Quintuple Point in Colloid-Polymer Mixtures. https://doi.org/10.1103/physrevlett.125.127803

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