Mean-field density-functional model of a second-order wetting transition

Area of Science:

• Physical Chemistry
• Surface Science
• Materials Science

Background:

• Wetting transitions describe how liquids spread on surfaces.
• Understanding the order of these transitions (first- or second-order) is crucial for predicting interfacial behavior.
• Existing models offer different predictions for these phenomena.

Purpose of the Study:

• To introduce and analyze a mean-field density-functional model for second-order wetting transitions.
• To contrast the behavior of second-order transitions with existing first-order models.
• To investigate interfacial properties and density variations near the contact line.

Main Methods:

• Development of a mean-field density-functional theory model.
• Numerical computation of interfacial and line tensions.
• Analysis of density profiles near the contact line.

Main Results:

• A mean-field density-functional model predicting second-order wetting transitions was developed.
• Interfacial and line tensions were numerically calculated, showing distinct behavior approaching the transition.
• Spatial variations in density near the contact line differed characteristically between first- and second-order transitions.

Conclusions:

• The new model provides a framework for understanding second-order wetting phenomena.
• The findings highlight key differences in interfacial behavior and density distributions at different transition orders.
• Results align with predictions from interface-displacement models, validating the current approach.