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Scaling laws for phase coexistence in multicomponent mixtures

Yicheng Qiang, Chengjie Luo, and David Zwicker*

  • *Contact author: david.zwicker@ds.mpg.de
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Phys. Rev. Research 7, 043008 – Published 1 October, 2025

DOI: https://doi.org/10.1103/zcvb-9t4b

Abstract

Liquid mixtures of many interacting components often exhibit numerous coexisting types of droplets. An exciting example is the cytosol of biological cells, where diverse droplets, known as condensates, enable cellular functions. However, how much their formation is constrained by thermodynamics is currently unclear because we lack predictions for generic multicomponent fluids. Linear stability analysis suggests that homogeneous mixtures become more robust to fluctuations as the number of components increases, so droplets might not form easily in multicomponent mixtures. In contrast, we show through numerical simulations and analytical scaling laws that the number of coexisting phases typically increases with the number of components in equilibrium. The combination of both results suggests that generic multicomponent mixtures can maintain many metastable states with various droplets, generalizing the nucleation-and-growth regime of binary mixtures. Our scaling laws also indicate why cells exhibit much fewer condensates than components and how they could exploit multistability to form various condensates independently.

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Phys. Rev. Research 7, 043008– Published 1 October, 2025
  • Received 2 May 2024
  • Accepted 8 September 2025
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI. Open access publication funded by Max Planck Society.

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