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Elastic Lennard-Jones polymers meet clusters: differences and similarities
Stefan Schnabel1, Michael Bachmann, Wolfhard Janke
1Institut für Theoretische Physik and Centre for Theoretical Sciences (NTZ), Universität Leipzig, Postfach 100920, D-04009 Leipzig, Germany. stefan.schnabel@itp.uni-leipzig.de
The Journal of Chemical Physics
|October 2, 2009
Summary
We studied polymer transitions using advanced simulations. Low-temperature polymer behavior strongly depends on size, resembling atomic clusters and showing specific icosahedral and non-icosahedral structures.
Area of Science:
- Polymer physics
- Computational materials science
- Statistical mechanics
Background:
- Understanding phase transitions in polymers is crucial for materials science.
- Off-lattice polymer models with specific interactions provide insights into complex material behaviors.
- The influence of system size on polymer morphology is not fully understood.
Purpose of the Study:
- To investigate solid-solid and solid-liquid transitions in flexible, off-lattice polymers.
- To analyze the effect of system size on low-temperature polymer behavior.
- To classify low-energy polymer structures, focusing on icosahedral and non-icosahedral morphologies.
Main Methods:
- Utilized advanced multicanonical Monte Carlo simulations.
- Employed models with Lennard-Jones monomer-monomer interactions.
- Incorporated anharmonic springs to represent polymer elasticity.
Main Results:
- Observed strong, non-monotonic dependence of low-temperature behavior on system size.
- Found broad similarities between polymer clusters and unbound atomic clusters.
- Successfully classified various low-energy polymer morphologies, including icosahedral and non-icosahedral structures.
Conclusions:
- System size is a critical factor influencing polymer phase transitions and low-temperature structures.
- The observed similarities suggest universal principles governing condensed matter systems.
- Detailed classification of polymer morphologies aids in understanding their physical properties.
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