Hard-sphere fluid mediated interaction: a pressure expression with application of the weighted correlation approach
2016 (English)In: Molecular Physics, ISSN 0026-8976, E-ISSN 1362-3028, Vol. 114, no 5, 599-607 p.Article in journal (Refereed) Published
By using a so-called differential-integral method on the chemical potential of a hard-sphere fluid, a special variant of our previously developed expression that describes the interaction between charged plates immersed in an electrolyte, is introduced to examine the hard-sphere fluid mediated pressure in a slit. The resulting expression consists of a kinetic contribution and a hard-sphere contribution, and it is formulated as a function of the single-particle direct correlation function and the density distribution of a hard-sphere fluid. It allows us to conveniently apply the classic density functional theory to explicitly investigate the influence of the hard-sphere excluded-volume effect on the interaction pressure between surfaces. In this study, a newly proposed weighted correlation approach (WCA)-Denton and Ashcroft (DA) method is employed to predict the interaction pressure as well as its pressure components for a hard-sphere fluid inside a slit pore. Comparisons with the results from the Monte Carlo simulations and the fundamental measure theory suggest that the WCA-DA method is able to accurately capture the detailed characteristic pattern of the pressure-separation curves at different fluid densities. It is also found, both qualitatively and quantitatively, that the hard-sphere pressure contribution dominates over the kinetic pressure contribution in determining the oscillatory behaviour of the interaction pressure curves, especially when a hard-sphere fluid of high density is concerned.
Place, publisher, year, edition, pages
2016. Vol. 114, no 5, 599-607 p.
Density functional theory, weighted correlation approach, hard-sphere fluid
Atom and Molecular Physics and Optics
IdentifiersURN: urn:nbn:se:hig:diva-20607DOI: 10.1080/00268976.2015.1105392ISI: 000372096500004ScopusID: 2-s2.0-84960226669OAI: oai:DiVA.org:hig-20607DiVA: diva2:872021
Funder: Swedish Nuclear Fuel and Waste Management Company (SKB)2015-11-172015-11-172016-04-15Bibliographically approved