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arXiv · 1701.02520

Mean field approach to first and second order phase transitions in ionic liquids

Sariel Bier·Nir Gavish·Hannes Uecker·Arik Yochelis
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Abstract

Ionic liquids are solvent-free electrolytes, some of which possess an intriguing self-assembly property. Using a mean-field framework (based on Onsager's relations) we show that bulk nano-structures arise via type-I and II phase transitions (PT), which directly affect the electrical double layer (EDL) structure. Ginzburg-Landau equation is derived and PT are related to temperature, potential and interactions. The type-I PT occurs for geometrically dissimilar anion/cation ratio and, surprisingly, is induced by perturbations on order of thermal fluctuations. Finally, we compare the insights with the decaying charge layers within the EDL, as widely observed in experiments.

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Sariel Bier, Nir Gavish, Hannes Uecker, Arik Yochelis. 2017-01-10. Mean field approach to first and second order phase transitions in ionic liquids. https://doi.org/10.1103/physreve.95.060201

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