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Synthesis of Cyclic Polymers and Characterization of Their Diffusive Motion in the Melt State at the Single Molecule Level
Published on: September 26, 2016
Demixing of a binary symmetric mixture studied with transition path sampling.
Elisabeth Schöll-Paschinger1, Christoph Dellago
1Department of Material Sciences and Process Engineering, University of Natural Resources and Life Sciences, Muthgasse 107, A-1190 Vienna, Austria. elisabeth.schoell-paschinger@boku.ac.at
The Journal of Chemical Physics
|September 21, 2010
Summary
We simulated nucleation in a binary fluid undergoing phase separation. Cluster density, not just composition, is key, influencing whether nucleation occurs via small or large clusters.
Area of Science:
- Thermodynamics
- Statistical Mechanics
- Computational Chemistry
Background:
- Phase transitions and nucleation are fundamental in physical chemistry.
- Understanding demixing transitions in binary fluids is crucial for materials science.
- Classical nucleation theory often simplifies complex nucleation mechanisms.
Purpose of the Study:
- To investigate the nucleation mechanism of the demixing transition in a binary symmetric Lennard-Jones fluid.
- To evaluate the suitability of the reaction coordinate used in classical nucleation theory.
- To analyze the properties of critical nuclei using transition path sampling.
Main Methods:
- Transition path sampling (TPS) simulations were employed.
- The nucleation process was studied by analyzing harvested paths.
- The transition state ensemble was determined to characterize critical nuclei.
Main Results:
- The study examined nucleation in a binary fluid with coexisting phases at equal densities but different compositions.
- The density of the growing cluster was found to be a critical factor in the nucleation pathway.
- Nucleation was observed to proceed through either small, compact clusters or large clusters with lower densities.
Conclusions:
- The density of the nucleating cluster significantly impacts the demixing transition mechanism.
- Classical nucleation theory's assumptions regarding the reaction coordinate may require refinement for such systems.
- Simulation results highlight the complex interplay of density and composition in fluid phase separation.
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