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arXiv · 1109.4667

Weak and Strong Coupling Theories for Polarizable Colloids and Nano-Particles

Amin Bakhshandeh·Alexandre Pereira dos Santos·Yan Levin
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Abstract

A theory is presented which allows us to accurately calculate the density profile of monovalent and multivalent counterions in suspensions of polarizable colloids or nano-particles. In the case of monovalent ions, we derive a weak-coupling theory that explicitly accounts for the ion-image interaction, leading to a modified Poisson-Boltzmann equation. For suspensions with multivalent counterions, a strong-coupling theory is used to calculate the density profile near the colloidal surface and a Poisson-Boltzmann equation with a renormalized boundary condition to account for the counterion distribution in the far-field. All the results are compared with the Monte Carlo simulations, showing an excellent agreement between the theory and the simulations.

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Amin Bakhshandeh, Alexandre Pereira dos Santos, Yan Levin. 2011-09-21. Weak and Strong Coupling Theories for Polarizable Colloids and Nano-Particles. https://doi.org/10.1103/physrevlett.107.107801

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