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arXiv · 1509.03814

Importance of Varying Permittivity on the Conductivity of Polyelectrolyte Solutions

Florian Fahrenberger·Owen A. Hickey·Jens Smiatek·Christian Holm
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Abstract

Dissolved ions can alter the local permittivity of water, nevertheless most theories and simulations ignore this fact. We present a novel algorithm for treating spatial and temporal variations in the permittivity and use it to measure the equivalent conductivity of a salt-free polyelectrolyte solution. Our new approach quantitatively reproduces experimental results unlike simulations with a constant permittivity that even qualitatively fail to describe the data. We can relate this success to a change in the ion distribution close to the polymer due to the built-up of a permittivity gradient.

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Florian Fahrenberger, Owen A. Hickey, Jens Smiatek, Christian Holm. 2015-09-13. Importance of Varying Permittivity on the Conductivity of Polyelectrolyte Solutions. https://doi.org/10.1103/physrevlett.115.118301

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