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Characterization of Thermal Transport in One-dimensional Solid Materials
Published on: January 26, 2014
On calculation of thermal conductivity from Einstein relation in equilibrium molecular dynamics
A Kinaci1, J B Haskins, T Çağın
1Material Science and Engineering, Texas A&M University, College Station, Texas 77845-3122, USA. akinaci@tamu.edu
The Journal of Chemical Physics
|July 12, 2012
Summary
This study introduces a new definition for integrated heat current, enabling the Einstein relation for calculating thermal conductivity in solids under periodic boundary conditions. This overcomes a key limitation of the method.
Area of Science:
- Computational Physics
- Materials Science
- Thermodynamics
Background:
- Equilibrium molecular dynamics (EMD) is a powerful tool for simulating material properties.
- The Einstein relation offers an alternative to the Green-Kubo relation for calculating thermal conductivity.
- A significant limitation of the Einstein relation is the lack of a clear definition for integrated heat current under periodic boundary conditions.
Purpose of the Study:
- To develop and validate a robust definition for integrated heat current within the Einstein relation framework.
- To enable the accurate calculation of thermal conductivity in solids using the Einstein relation under periodic boundary conditions.
- To compare the performance and results of the enhanced Einstein relation with the established Green-Kubo method.
Main Methods:
- Developed a novel definition for integrated heat current suitable for periodic boundary conditions in EMD simulations.
- Applied the refined Einstein relation to calculate the thermal conductivity of solid argon and silicon-based systems.
- Conducted comparative analysis against the Green-Kubo approach for validation.
Main Results:
- Successfully implemented the Einstein relation for thermal conductivity calculations under periodic boundary conditions.
- Obtained comparable results for thermal conductivity in solid argon and silicon systems using both the enhanced Einstein relation and Green-Kubo methods.
- Demonstrated the practical applicability of the developed integrated heat current definition.
Conclusions:
- The proposed definition of integrated heat current effectively extends the applicability of the Einstein relation for thermal conductivity calculations in EMD.
- This advancement provides a viable alternative to the Green-Kubo method, particularly when analytical heat current expressions are challenging.
- The findings pave the way for broader adoption of the Einstein relation in solid-state thermal transport simulations.
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