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arXiv · 2509.25583

Contact Forces in Microgel Suspensions

Fran Ivan Vrban·Antonio Šiber·Primož Ziherl
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Abstract

Within a model where micrometer-size soft colloidal particles are viewed as liquid drops, we theoretically study the contact interaction between them. We compute the exact deformation energy across a broad range of indentations and for various model parameters, and we show that it can be reproduced using truncated superball and spheropolyhedral variational shapes in the attractive and the repulsive regime, respectively. At large surface tensions representative of microgels, this energy is pairwise additive well beyond small indentations and can be approximated by a power-law dependence on indentation with an exponent around 2.

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Fran Ivan Vrban, Antonio Šiber, Primož Ziherl. 2025-09-29. Contact Forces in Microgel Suspensions. https://arxiv.org/abs/2509.25583

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