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arXiv · 0706.2956

Density-dependent interactions and structure of charged colloidal dispersions in the weak screening regime

Luis F. Rojas-Ochoa·Ramon Castaneda-Priego·Vladimir Lobaskin·Anna Stradner·Frank Scheffold·Peter Schurtenberger
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Abstract

We determine the structure of charge-stabilized colloidal suspensions at low ionic strength over an extended range of particle volume fractions using a combination of light and small angle neutron scattering experiments. The variation of the structure factor with concentration is analyzed within a one-component model of a colloidal suspension. We show that the observed structural behavior corresponds to a non-monotonic density dependence of the colloid effective charge and the mean interparticle interaction energy. Our findings are corroborated by similar observations from primitive model computer simulations of salt-free colloidal suspensions.

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Luis F. Rojas-Ochoa, Ramon Castaneda-Priego, Vladimir Lobaskin, Anna Stradner, Frank Scheffold, Peter Schurtenberger. 2008-04-10. Density-dependent interactions and structure of charged colloidal dispersions in the weak screening regime. https://doi.org/10.1103/physrevlett.100.178304

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