Prediction of the concentration dependence of the surface tension and density of salt solutions : atomistic simulations with polarizable and nonpolarizable models

• Published in: Physical chemistry chemical physics : PCCP Vol. 2013; no. 15; pp. 11679 - 11690
• Main Authors: Neyt, Jean-Claude, Wender, Aurélie, Lachet, Véronique, Ghoufi, Aziz, Malfreyt, Patrice
• Format: Journal Article
• Language: English
• Published: Royal Society of Chemistry 16.05.2013
• Subjects: Chemical Physics; Physics
• ISSN: 1463-9076; 1463-9084
• DOI: 10.1039/C3CP50904D

Molecular simulations using polarizable and nonpolarizable models for water and ions are carried out to predict the dependence of the surface tension on salt concentration. The polarizable water and ion models are based on the classical Drude oscillators. The temperature dependence of the surface tension of water is examined for the different water models. The dependence of salt densities on salt concentration is investigated through the nonpolarizable and polarizable models. Lastly, the reproduction of the surface tension of salt solution over a large range of concentration is analyzed through a number of combinations between ions and water force fields. The structure of the interface is then discussed as a function of the polarization effects. We establish here the inability of the polarizable force fields based on the classical Drude oscillators to reproduce the salt concentration dependence of surface tension of NaCl aqueous solutions.