Gibbs paradox and a possible mechanism of like-charge attraction in colloids

Chi-Lun Lee; Yiing-Rei Chen

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arXiv · 1201.0069

Gibbs paradox and a possible mechanism of like-charge attraction in colloids

Chi-Lun Lee·Yiing-Rei Chen

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Abstract

Based on a reconsideration of the Gibbs paradox, we show that a residual, non-extensive term in entropy turns up upon mixing identical particles, whether they are indistinguishable or not. The positive contribution from this residual entropy leads to a decrease in free energy, and we suggest that this entropic mechanism may serve as a source of like-charge attractions between a pair of colloidal particles or other macroions. For a system of two colloidal particles along with their neutralizing counterions, such decrease in free energy is of a few thermal energies and therefore crucial to the effective interaction between the particles.

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Chi-Lun Lee, Yiing-Rei Chen. 2011-12-30. Gibbs paradox and a possible mechanism of like-charge attraction in colloids. https://arxiv.org/abs/1201.0069

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