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Title: Effect of water on the local electric potential of simulated ionic micelles

Abstract

Ionic micelles in an aqueous solution containing single-charged counter-ions have been simulated by molecular dynamics. For both cationic and anionic micelles, it has been demonstrated that explicit description of solvent has strong effect on the micelle’s electric field. The sign of the local charge alters in the immediate vicinity of the micellar crown and the electric potential varies nonmonotonically. Two micelle models have been examined: the hybrid model with a rigid hydrocarbon core and the atomistic model. For three molecular models of water (Simple Point Charge model (SPC), Transferable Intermolecular Potential 5- Points (TIP5P) and two-centered S2), the results have been compared with those for the continuum solvent model. The orientational ordering of solvent molecules has strong effect on the local electric field surprisingly far from the micelle surface.

Authors:
;  [1]
  1. Institute of Chemistry, St. Petersburg State University, Universitetskiy pr. 26, Petrodvoretz, St. Petersburg 198504 (Russian Federation)
Publication Date:
OSTI Identifier:
22493472
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Chemical Physics; Journal Volume: 143; Journal Issue: 4; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; AQUEOUS SOLUTIONS; COMPARATIVE EVALUATIONS; COMPUTERIZED SIMULATION; ELECTRIC FIELDS; ELECTRIC POTENTIAL; HYDROCARBONS; MICELLAR SYSTEMS; MOLECULAR DYNAMICS METHOD; MOLECULAR MODELS; MOLECULES; POINT CHARGE; POTENTIALS; SOLVENTS; SURFACES; WATER

Citation Formats

Brodskaya, Elena N., and Vanin, Alexander A., E-mail: alexvanin@yandex.ru. Effect of water on the local electric potential of simulated ionic micelles. United States: N. p., 2015. Web. doi:10.1063/1.4927089.
Brodskaya, Elena N., & Vanin, Alexander A., E-mail: alexvanin@yandex.ru. Effect of water on the local electric potential of simulated ionic micelles. United States. doi:10.1063/1.4927089.
Brodskaya, Elena N., and Vanin, Alexander A., E-mail: alexvanin@yandex.ru. Tue . "Effect of water on the local electric potential of simulated ionic micelles". United States. doi:10.1063/1.4927089.
@article{osti_22493472,
title = {Effect of water on the local electric potential of simulated ionic micelles},
author = {Brodskaya, Elena N. and Vanin, Alexander A., E-mail: alexvanin@yandex.ru},
abstractNote = {Ionic micelles in an aqueous solution containing single-charged counter-ions have been simulated by molecular dynamics. For both cationic and anionic micelles, it has been demonstrated that explicit description of solvent has strong effect on the micelle’s electric field. The sign of the local charge alters in the immediate vicinity of the micellar crown and the electric potential varies nonmonotonically. Two micelle models have been examined: the hybrid model with a rigid hydrocarbon core and the atomistic model. For three molecular models of water (Simple Point Charge model (SPC), Transferable Intermolecular Potential 5- Points (TIP5P) and two-centered S2), the results have been compared with those for the continuum solvent model. The orientational ordering of solvent molecules has strong effect on the local electric field surprisingly far from the micelle surface.},
doi = {10.1063/1.4927089},
journal = {Journal of Chemical Physics},
number = 4,
volume = 143,
place = {United States},
year = {Tue Jul 28 00:00:00 EDT 2015},
month = {Tue Jul 28 00:00:00 EDT 2015}
}
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