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arXiv · 2009.08544

Charge-regulation effects in nanoparticle self-assembly

Tine Curk·Erik Luijten
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Abstract

Nanoparticles in solution acquire charge through dissociation or association of surface groups. Thus, a proper description of their electrostatic interactions requires the use of charge-regulating boundary conditions rather than the commonly employed constant-charge approximation. We implement a hybrid Monte Carlo/Molecular Dynamics scheme that dynamically adjusts the charges of individual surface groups of objects while evolving their trajectories. Charge-regulation effects are shown to qualitatively change self-assembled structures due to global charge redistribution, stabilizing asymmetric constructs. We delineate under which conditions the conventional constant-charge approximation may be employed and clarify the interplay between charge regulation and dielectric polarization.

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Tine Curk, Erik Luijten. 2021-02-09. Charge-regulation effects in nanoparticle self-assembly. https://doi.org/10.1103/physrevlett.126.138003

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