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Updated: Jun 27, 2025
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An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
Published on: December 4, 2017
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Characterizing Microheterogeneity in Liquid Mixtures via Local Density Fluctuations
Michael Lass1, Tobias Kenter1, Christian Plessl1
1Faculty of Computer Science, Electrical Engineering and Mathematics, Department of Computer Science, Paderborn University, Warburger Straße 100, 33098 Paderborn, Germany.
Entropy (Basel, Switzerland)
|April 26, 2024
Summary
This study introduces a new computational method to analyze microheterogeneity in liquid mixtures using density fluctuations. The approach effectively reveals domain formation in ionic liquids and estimates configuration entropy.
Area of Science:
- Computational chemistry
- Materials science
- Statistical mechanics
Background:
- Complex liquid mixtures exhibit microheterogeneity and microphase separation.
- Understanding these phenomena is crucial for predicting material properties.
- Existing analysis methods may lack sensitivity or broad applicability.
Purpose of the Study:
- To develop and present a novel post-processing method for characterizing microheterogeneity in simulations.
- To quantify microphase separation based on local density fluctuations.
- To provide a versatile tool applicable to various simulation techniques.
Main Methods:
- Utilizing local density fluctuations of constituents within sampling spheres of variable size.
- Applying multidimensional correlation of density distributions.
- Implementing the method for molecular dynamics (MD) and Monte Carlo (MC) simulations.
Main Results:
- Successfully characterized microheterogeneity and domain formation in imidazolium-based ionic liquids.
- Demonstrated the method's sensitivity and advantages over existing techniques.
- Enabled estimation of configuration entropy and investigation of system voids.
Conclusions:
- The novel approach provides a clear picture of domain formation in complex liquids.
- The method is broadly applicable to MD and MC simulations, including those with periodic boundary conditions.
- The analysis tool is available as free software (TRAVIS).
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