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Accurate Determination of the Equilibrium Surface Tension Values with Area Perturbation Tests
Published on: August 30, 2019
Computation of surface tensions using expanded ensemble simulations
1Departamento de Física Aplicada, Facultad de Ciencias Experimentales, Universidad de Huelva, 21071 Huelva, Spain. demiguel@uhu.es
The Journal of Physical Chemistry. B
|March 25, 2008
Summary
This study introduces a direct simulation method for surface tension using expanded ensemble simulations. The technique accurately calculates interfacial tension for various fluid models, including those with discontinuous interactions.
Area of Science:
- Computational physics and chemistry
- Materials science
- Thermodynamics
Background:
- Accurate simulation of surface tension is crucial for understanding fluid behavior at interfaces.
- Existing methods for calculating interfacial tension can have limitations, especially for systems with discontinuous interactions.
Purpose of the Study:
- To examine a novel method for the direct simulation of surface tension.
- To assess the general applicability and accuracy of the expanded ensemble simulation method for interfacial tension calculations across different model fluids.
Main Methods:
- Utilized the thermodynamic route to interfacial tension.
- Employed the expanded ensemble simulation method to calculate free energy differences between inhomogeneous systems with varying interfacial areas.
- Applied the method to planar vapor-liquid interfaces of Lennard-Jones, Lennard-Jones dimers, Gay-Berne, and square-well model fluids.
Main Results:
- The expanded ensemble method successfully computed interfacial tension for both continuous and discontinuous interaction potentials.
- The method demonstrated no asymmetry issues for discontinuous interactions, unlike the test area method.
- Results showed good agreement when compared with data from mechanical and test area simulation techniques.
Conclusions:
- The direct simulation method based on expanded ensemble simulations is a general and accurate approach for calculating surface tension.
- This technique offers advantages for systems with discontinuous interactions, providing a reliable alternative to existing methods.
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