Drying layer near a weakly attractive surface

Abstract

Depletion of the liquid density near a solid surface with a weak long-range fluid-surface interaction was studied by computer simulations of the liquid-vapor coexistence of a LJ fluid confined in slitlike pores. In a wide temperature range the liquid density decreases towards the surface without the formation of a {\it vapor} layer between the liquid and the solid surface. This evidences the absence of a drying transition up to the liquid-vapor critical point. Two contributions to the excess desorption {\it ${\Gamma }_{tot}$} were found. The first one {\it ${\Gamma }_{\xi }$} $\sim$ ${\rho }_{bulk}$ $\xi$ exists at any temperature and diverges as the bulk correlation length $\xi$ when approaching the liquid-vapor critical temperature {\it {T${}_c$}}. The second contribution {\it ${\Gamma }_L$} $\sim$ ${\rho }_{bulk}$ {\it L${}_0$} originates from a microscopic {\it drying layer} near the solid boundary. At high temperatures the thickness {\it L${}_0$} of the drying layer increases in accordance with the power law {\it L${}_0$ $\sim$ - ln (1-T/T${}_c$)}, indicating a drying transition at {\it {T${}_c$}}. The {\it drying layer} can be suppressed by strengthening the fluid-surface interaction, by increasing the fluid-surface interaction range or by decreasing the pore size.

24 pages, 15 figures

References in corpus (1)

• Surface critical behavior of fluids: Lennard-Jones fluid near weakly attractive substrate

Cited by in corpus (4)

• Critical Drying of Liquids
• Drying and Wetting Transitions of a Lennard-Jones Fluid: Simulations and Density Functional Theory
• Phase diagram and structure of colloid-polymer mixtures confined between walls
• Critical surface adsorption of confined binary liquids with locally conserved mass and composition