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dc.contributor.advisorSchlossman, Mark L.en_US
dc.contributor.authorLaanait, Nouamaneen_US
dc.date.accessioned2012-12-07T22:20:53Z
dc.date.available2012-12-07T22:20:53Z
dc.date.created2011-12en_US
dc.date.issued2012-12-07
dc.date.submitted2011-12en_US
dc.identifier.urihttp://hdl.handle.net/10027/8956
dc.description.abstractIon correlations have been suggested as the underlying mechanism of a number of counterintuitive phenomena in soft condensed-matter, such as like-charge attraction. Recently, several theoretical models have emerged, attempting to address these electrostatic correlations, beyond the mean field description of the Poisson-Boltzmann theory. The central prediction of these theories, the ion density profile, has remained untested by measurements with microscopic resolution. In this work, we present the first molecular-level tests of an ion correlations model. Analysis of synchrotron x-ray reflectivity using a phenomenological model reveals ion condensation at the liquid/liquid interface, when polarized with an electric field. Tuning the density of this ionic layer allows for a detailed study of ion correlations as a function of the Coulomb coupling strength in the system. We propose a density functional theory that aims to describe electrostatic ion correlations and explicitly includes solvent effects through an ion-solvent interaction potential, mapped out using Molecular Dynamics simulations. The proposed model predicts global electrostatic properties of the system that are in excellent agreement with thermodynamic measurements of the interfacial excess charge, with no adjustable parameters. Comparison of the density profiles to the x-ray data indicates that a nonlocal free functional based on the Debye-Huckel-Hole theory of a one-component plasma, adequately describes ion-ion interactions up to a correlation strength of 4 k_B T. We anticipate this result to be of relevance in other strongly correlated soft matter systems.en_US
dc.language.isoenen_US
dc.rightsen_US
dc.rightsCopyright 2011 Nouamane Laanaiten_US
dc.subjectElectrical Double Layeren_US
dc.subjectPoisson-Boltzmannen_US
dc.subjectIon distributionsen_US
dc.subjectX-ray reflectivityen_US
dc.subjectliquid/liquid interfaceen_US
dc.subjectMolecular Dynamicsen_US
dc.subjectIon Correlationsen_US
dc.titleIon Correlations at Electrified Soft Matter Interfacesen_US
thesis.degree.departmentPhysicsen_US
thesis.degree.disciplinePhysicsen_US
thesis.degree.grantorUniversity of Illinois at Chicagoen_US
thesis.degree.levelDoctoralen_US
thesis.degree.namePhD, Doctor of Philosophyen_US
dc.type.genrethesisen_US
dc.contributor.committeeMemberStephanov, Mikhail A.en_US
dc.contributor.committeeMemberPerez-Salas, Ursula A.en_US
dc.contributor.committeeMemberVanysek, Petren_US
dc.contributor.committeeMemberFenter, Paulen_US
dc.type.materialtexten_US


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