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Accurate Determination of the Equilibrium Surface Tension Values with Area Perturbation Tests
Published on: August 30, 2019
Density functional calculations of surface free energies
H Fox1, A P Horsfield, M J Gillan
1Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT, UK. h.fox@ucl.ac.uk
The Journal of Chemical Physics
|April 15, 2006
Summary
We developed a thermodynamic integration method to calculate surface free energy using strain and molecular dynamics. This approach accurately determines surface energy for materials like titanium dioxide across various temperatures.
Area of Science:
- Materials Science
- Computational Chemistry
- Thermodynamics
Background:
- Calculating surface free energy is crucial for understanding material properties.
- Existing methods may have limitations in accuracy or applicability.
Purpose of the Study:
- To introduce a general thermodynamic integration method for determining surface free energy.
- To validate the method using first-principles density functional theory (DFT) calculations.
Main Methods:
- Thermodynamic integration with strain as the integration parameter.
- Molecular dynamics simulations to obtain thermal average stress.
- Temperature integration to model temperature dependence of free surface energy.
- Application to the titanium dioxide (110) surface.
Main Results:
- The method accurately calculates surface free energy, showing excellent agreement with DFT at zero temperature.
- Calculations at 295 K and 1000 K also demonstrated high accuracy between different integration approaches.
- A linear relationship for temperature dependence of free surface energy was established.
Conclusions:
- The proposed thermodynamic integration method offers a robust and accurate way to compute surface free energy.
- This approach is applicable to various materials and temperatures, advancing surface science studies.
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