To the top

Page Manager: Webmaster
Last update: 9/11/2012 3:13 PM

Tell a friend about this page
Print version

Packing frustration in de… - University of Gothenburg, Sweden Till startsida
Sitemap
To content Read more about how we use cookies on gu.se

Packing frustration in dense confined fluids

Journal article
Authors Kim Nygård
Sten Sarman
Roland Kjellander
Published in Journal of Chemical Physics
Volume 141
Issue 9
Pages 094501
ISSN 0021-9606
Publication year 2014
Published at Department of Chemistry and Molecular Biology
Pages 094501
Language en
Links dx.doi.org/10.1063/1.4894137
https://gup.ub.gu.se/file/135697
Keywords liquid structure, inhomogeneous fluid, packing frustration, pair distribution, integral equation theory
Subject categories Surfaces and interfaces, Liquid physics, Mesoscopic physics, Physical Chemistry, Surface and colloid chemistry, Chemical physics, Statistical mechanics

Abstract

Packing frustration for confined fluids, i.e., the incompatibility between the preferred packing of the fluid particles and the packing constraints imposed by the confining surfaces, is studied for a dense hard-sphere fluid confined between planar hard surfaces at short separations. The detailed mechanism for the frustration is investigated via an analysis of the anisotropic pair distributions of the confined fluid, as obtained from integral equation theory for inhomogeneous fluids at pair correlation level within the anisotropic Percus-Yevick approximation. By examining the mean forces that arise from interparticle collisions around the periphery of each particle in the slit, we calculate the principal components of the mean force for the density profile – each component being the sum of collisional forces on a particle's hemisphere facing either surface. The variations of these components with the slit width give rise to rather intricate changes in the layer structure between the surfaces, but, as shown in this paper, the basis of these variations can be easily understood qualitatively and often also semi-quantitatively. It is found that the ordering of the fluid is in essence governed locally by the packing constraints at each single solid-fluid interface. A simple superposition of forces due to the presence of each surface gives surprisingly good estimates of the density profiles, but there remain nontrivial confinement effects that cannot be explained by superposition, most notably the magnitude of the excess adsorption of particles in the slit relative to bulk.

Page Manager: Webmaster|Last update: 9/11/2012
Share:

The University of Gothenburg uses cookies to provide you with the best possible user experience. By continuing on this website, you approve of our use of cookies.  What are cookies?