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Phase Transitions of Soluble Surfactants at a Liquid-Vapor Interface

M. S. Tomassone·A. Couzis·C. Maldarelli·J. R. Banavar·J. Koplik
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Abstract

Although medium chain length insoluble amphiphiles are well known to form gaseous and liquid expanded phases on an air/water interface, the situation for the soluble case is less clear. We perform molecular dynamics simulations of model surfactant molecules dissolved in a bulk liquid solvent in coexistence with its vapor. Our results indicate a transition in both soluble and insoluble surfactants: a plateau in surface tension vs. surface coverage, whose instantaneous configurations display two phase coexistence, along with correlation functions indicating a transition to gaseous to liquid-like behavior.

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M. S. Tomassone, A. Couzis, C. Maldarelli, J. R. Banavar, J. Koplik. 2000-11-10. Phase Transitions of Soluble Surfactants at a Liquid-Vapor Interface. https://arxiv.org/abs/cond-mat/0011189

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