Describing screening in dense ionic fluids with a charge-frustrated Ising model

Nicholas B. Ludwig; Kinjal Dasbiswas; Dmitri V. Talapin; Suriyanarayanan Vaikuntanathan

doi:10.1063/1.5043410

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arXiv · 1810.00918

Describing screening in dense ionic fluids with a charge-frustrated Ising model

Nicholas B. Ludwig·Kinjal Dasbiswas·Dmitri V. Talapin·Suriyanarayanan Vaikuntanathan

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Abstract

Charge correlations in dense ionic fluids give rise to novel effects such as long-range screening and colloidal stabilization which are not predicted by the classic Debye-Huckel theory. We show that a Coulomb or charge-frustrated Ising model, which accounts for both long-range Coulomb and short-range molecular interactions, simply describes some of these ionic correlations. In particular, we obtain at mean field level and in simulations, a non-monotonic dependence of the screening length on the temperature. Using a combination of simulations and mean field theories, we study how the correlations in the various regimes are affected by the strength of the short ranged interactions.

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Nicholas B. Ludwig, Kinjal Dasbiswas, Dmitri V. Talapin, Suriyanarayanan Vaikuntanathan. 2018-10-30. Describing screening in dense ionic fluids with a charge-frustrated Ising model. https://doi.org/10.1063/1.5043410

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