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arXiv · 1303.2508

AC-field-induced Polarization for Uncharged Colloids in Salt Solution: A Dissipative Particle Dynamics Simulation

Jiajia Zhou·Friederike Schmid
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Abstract

We study the response of a spherical colloid under alternating electric fields (AC-fields) by mesoscopic simulation method, accounting in full for hydrodynamic and electrostatic interactions. We focus on a special case of uncharged colloids. The main polarization mechanism is the "volume-polarization", where ionic currents are deflected by the core of the uncharged colloid. Specifically, we compute the polarizability of a single colloid and systematically investigate the effect of AC field frequency and salt concentration. The simulation results are compared with predictions from classical Maxwell-Wagner theory and electrokinetic theory.

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Jiajia Zhou, Friederike Schmid. 2013-04-16. AC-field-induced Polarization for Uncharged Colloids in Salt Solution: A Dissipative Particle Dynamics Simulation. https://doi.org/10.1140/epje%2Fi2013-13033-0

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