Efficient and realistic simulation of phase coexistence
G J A Sevink1, E M Blokhuis1, X Li1
1Leiden Institute of Chemistry, Leiden University, P.O. Box 9502, 2300 RA Leiden, The Netherlands.
The Journal of Chemical Physics
|December 31, 2020
Summary
We adapted the hybrid particle field-molecular dynamics (hPF-MD) method for compressible systems. This enables simulations of phenomena like evaporation and crystallization, offering new insights into non-uniform density behaviors.
Area of Science:
- Computational physics
- Materials science
- Chemical engineering
Background:
- Existing multi-scale methods often struggle with compressible systems.
- Simulating phenomena like evaporation and crystallization requires handling non-uniform densities.
- The hybrid particle field-molecular dynamics (hPF-MD) method offers efficient treatment of intermolecular interactions.
Purpose of the Study:
- To adapt the hPF-MD method for simulating compressible systems.
- To implement equations of state (EOS) into hPF-MD for non-uniform density phenomena.
- To compare compressible hPF-MD with its mean-field counterpart.
Main Methods:
- Implementation of new equations of state (EOS) into hPF-MD.
- Adaptation of hPF-MD for compressible systems.
- Comparison with mean-field approaches using Cell Model and Carnahan-Starling EOS.
- Analysis of particle-based parameters and particle-to-field projection.
Main Results:
- The adapted hPF-MD method successfully simulates compressible systems.
- Particle density per field grid cell is identified as a key parameter.
- Gaussian kernel projection is shown to be superior to cloud-in-cell projection.
- hPF-MD exhibits non-classical behavior near the critical point.
Conclusions:
- The adapted hPF-MD method is suitable for simulating phenomena involving non-uniform densities, such as evaporation and crystallization.
- The choice of particle-to-field projection method significantly impacts simulation accuracy.
- Compressible hPF-MD shows promise for studying critical phenomena in materials.
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