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Simulation of fluid-solid coexistence via thermodynamic integration using a modified cell model
Michael Nayhouse1, Ankur M Amlani, Vincent R Heng
1Department of Chemical and Biomolecular Engineering, University of California, Los Angeles, CA 90095, USA.
Journal of Physics. Condensed Matter : an Institute of Physics Journal
|February 28, 2012
Summary
This study introduces an improved thermodynamic integration technique to efficiently simulate fluid-solid transitions. The method reduces computational cost while accurately capturing size effects crucial for understanding phase behavior.
Area of Science:
- Computational physics
- Materials science
- Statistical mechanics
Background:
- Simulating fluid-solid transitions accurately remains challenging despite advances in computational methods.
- Thermodynamic integration is a common technique but requires simulating numerous states, increasing computational cost.
- Existing methods often overlook the significant impact of system size on simulation results.
Purpose of the Study:
- To develop and validate a modified thermodynamic integration technique that reduces the number of simulated states.
- To accurately determine the free energy difference between fluid and solid phases.
- To investigate and account for size-dependent effects in fluid-solid transition simulations.
Main Methods:
- A modified cell model, inspired by Hoover and Ree, was employed to link fluid and solid phases.
- Constant-pressure simulations were performed using a tunable external field to facilitate phase transitions.
- Histogram reweighting and finite-size scaling techniques were applied to analyze simulation data and size effects.
Main Results:
- The proposed thermodynamic integration technique successfully reduced the number of simulated states.
- Direct determination of free energy differences between phases was achieved via histogram reweighting.
- Size-dependent analysis revealed the critical importance of accounting for finite-size effects in simulations.
Conclusions:
- The modified thermodynamic integration method offers a more efficient approach to studying fluid-solid coexistence.
- Finite-size scaling analysis is essential for accurate simulations of fluid-solid transitions.
- This work provides a robust framework for future simulations of phase transitions in materials.
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