Surface viscosity of liquid interfaces from Green-Kubo relations
Pál Jedlovszky1, Marcello Sega2
1Department of Chemistry, Eszterházy Károly Catholic University, Leányka Utca 12, H-3300 Eger, Hungary.
The Journal of Chemical Physics
|May 22, 2024
Summary
This study introduces a new method to directly measure surface viscosity in liquids. It uses molecular dynamics simulations to distinguish surface layer viscosity from bulk viscosity for better understanding of interfacial dynamics.
Area of Science:
- Physical Chemistry
- Surface Science
- Computational Fluid Dynamics
Background:
- Precise determination of surface transport coefficients is crucial for processes like atmospheric chemistry and catalysis.
- Previous work indicated reduced surface viscosity in simple liquids through surface excitation dispersion relations.
Purpose of the Study:
- To develop and present a novel, direct method for measuring surface viscosity.
- To differentiate viscosity contributions from the surface layer versus the bulk liquid.
Main Methods:
- Utilized modified Green-Kubo relations adapted for inhomogeneous systems.
- Employed extensive molecular dynamics simulations.
- Analyzed viscosity contributions from fluid slabs of varying thicknesses.
Main Results:
- Successfully quantified viscosity contributions from different fluid slab thicknesses.
- Demonstrated an independent measure to distinguish surface viscosity from bulk viscosity.
- Provided a more detailed understanding of interfacial dynamics.
Conclusions:
- The developed method offers an accurate and independent way to measure surface viscosity.
- This approach enhances the understanding of interfacial transport coefficients.
- The findings are applicable to various fields relying on liquid interface properties.
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