Surface Phase Diagrams for Wetting with Long-Ranged Forces

Area of Science:

• Physics
• Physical Chemistry
• Materials Science

Background:

• Recent studies using density functional theory and simulations have questioned the universality of established surface phase diagrams for wetting and drying transitions.
• These prior models, particularly those by Nakanishi and Fisher, were primarily developed for systems with short-ranged forces and may not apply to systems with long-ranged, dispersionlike forces.

Purpose of the Study:

• To extend the understanding of wetting and drying transitions in systems with long-ranged forces.
• To derive fully analytic results for surface phase diagrams across the entire temperature range up to the bulk critical temperature (Tc).
• To precisely determine the nature of phase boundaries, the order of transitions, and the asymmetry between wetting and drying lines.

Main Methods:

• Theoretical derivation of analytic results.
• Analysis of density functional theory and simulation data.
• Investigation of systems with long-ranged, dispersionlike forces.

Main Results:

• The study successfully derives complete analytic surface phase diagrams for wetting and drying transitions up to the critical temperature (Tc).
• Exact determination of phase boundaries, transition orders, and asymmetries between wetting and drying lines.
• Demonstration that these transition lines converge to an ordinary surface critical point.
• Identification and exact characterization of critical singularities for lines of maximally multicritical wetting and drying transitions.

Conclusions:

• The derived analytic surface phase diagrams provide a comprehensive description for systems with long-ranged forces, extending beyond previous models.
• The findings confirm the convergence of wetting and drying transition lines to a surface critical point.
• The study highlights the significance of multicritical phenomena in understanding surface phase behavior.