Wetting of prototypical one and twodimensional systems: Thermodynamics and density functional theory
Abstract
Consider a twodimensional capped capillary pore formed by capping two parallel planar walls with a third wall orthogonal to the two planar walls. This system reduces to a slit pore sufficiently far from the capping wall and to a single planar wall when the side walls are far apart. Not surprisingly, wetting of capped capillaries is related to wetting of slit pores and planar walls. For example, the wetting temperature of the capped capillary provides the boundary between firstorder and continuous transitions to condensation. We present a numerical investigation of adsorption in capped capillaries of mesoscopic widths based on density functional theory. The fluidfluid and fluidsubstrate interactions are given by the pairwise LennardJones potential. We also perform a parametric study of wetting in capped capillaries by a liquid phase by varying the applied chemical potential, temperature, and pore width. This allows us to construct surface phase diagrams and investigate the complicated interplay of wetting mechanisms specific to each system, in particular, the dependence of capillary wetting temperature on the pore width.
 Authors:
 Department of Chemical Engineering, Imperial College London, London SW7 2AZ (United Kingdom)
 (United Kingdom)
 Publication Date:
 OSTI Identifier:
 22416026
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Journal of Chemical Physics; Journal Volume: 142; Journal Issue: 3; 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; ADSORPTION; CAPILLARIES; DENSITY FUNCTIONAL METHOD; LENNARDJONES POTENTIAL; LIQUIDS; PARAMETRIC ANALYSIS; PHASE DIAGRAMS; SUBSTRATES; SURFACES; THERMODYNAMICS; TWODIMENSIONAL SYSTEMS
Citation Formats
Yatsyshin, Petr, Kalliadasis, Serafim, Savva, Nikos, and School of Mathematics, Cardiff University, Cardiff CF24 4AG. Wetting of prototypical one and twodimensional systems: Thermodynamics and density functional theory. United States: N. p., 2015.
Web. doi:10.1063/1.4905605.
Yatsyshin, Petr, Kalliadasis, Serafim, Savva, Nikos, & School of Mathematics, Cardiff University, Cardiff CF24 4AG. Wetting of prototypical one and twodimensional systems: Thermodynamics and density functional theory. United States. doi:10.1063/1.4905605.
Yatsyshin, Petr, Kalliadasis, Serafim, Savva, Nikos, and School of Mathematics, Cardiff University, Cardiff CF24 4AG. 2015.
"Wetting of prototypical one and twodimensional systems: Thermodynamics and density functional theory". United States.
doi:10.1063/1.4905605.
@article{osti_22416026,
title = {Wetting of prototypical one and twodimensional systems: Thermodynamics and density functional theory},
author = {Yatsyshin, Petr and Kalliadasis, Serafim and Savva, Nikos and School of Mathematics, Cardiff University, Cardiff CF24 4AG},
abstractNote = {Consider a twodimensional capped capillary pore formed by capping two parallel planar walls with a third wall orthogonal to the two planar walls. This system reduces to a slit pore sufficiently far from the capping wall and to a single planar wall when the side walls are far apart. Not surprisingly, wetting of capped capillaries is related to wetting of slit pores and planar walls. For example, the wetting temperature of the capped capillary provides the boundary between firstorder and continuous transitions to condensation. We present a numerical investigation of adsorption in capped capillaries of mesoscopic widths based on density functional theory. The fluidfluid and fluidsubstrate interactions are given by the pairwise LennardJones potential. We also perform a parametric study of wetting in capped capillaries by a liquid phase by varying the applied chemical potential, temperature, and pore width. This allows us to construct surface phase diagrams and investigate the complicated interplay of wetting mechanisms specific to each system, in particular, the dependence of capillary wetting temperature on the pore width.},
doi = {10.1063/1.4905605},
journal = {Journal of Chemical Physics},
number = 3,
volume = 142,
place = {United States},
year = 2015,
month = 1
}

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