Dynamics of Binary Mixtures with Ions: Dynamic Structure Factor and Mesophase Formation

Abstract

Dynamic equations are presented for polar binary mixtures containing ions in the presence of the preferential solvation. In one-phase states, we calculate the dynamic structure factor of the composition accounting for the ion motions. Microphase separation can take place for sufficiently large solvation asymmetry of the cations and the anions. We show two-dimensional simulation results of the mesophase formation with an antagonistic salt, where the cations are hydrophilic and the anions are hydrophobic. The structure factor S(q) in the resultant mesophase has a sharp peak at an intermediate wave number on the order of the Debye-Huckel wave number. As the quench depth is increased, the surface tension nearly vanishes in mesophases due to an electric double layer.

24 pages, 10 figures, to appear in Journal of Physics: Condensed Matter

References in corpus (7)

• Electrostatic correlations: from Plasma to Biology
• Solvation Effects in Near-Critical Binary Mixtures
• Surface tension of electrolytes: Hydrophilic and hydrophobic ions near an interface
• Liquid-liquid interfacial tension of electrolyte solutions
• Nonionic and ionic surfactants at an interface
• Phase-Separation Transition in Liquid Mixtures Near Charged Objects
• Stability of additive-free water-in-oil emulsions

Cited by in corpus (6)

• Charged colloids in an aqueous mixture with a salt
• Precipitation in aqueous mixtures with addition of strongly hydrophilic or hydrophobic solute
• Structure Formation due to Antagonistic Salts
• Solvation Effects in Phase Transitions in Soft Matter
• How antagonistic salts cause nematic ordering and behave like diblock copolymers
• The vanishing water/oil interface in the presence of antagonistic salt