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Models for twistable elastic polymers in Brownian dynamics, and their implementation for LAMMPS
C A Brackley1, A N Morozov1, D Marenduzzo1
1SUPA, School of Physics and Astronomy, University of Edinburgh, Mayfield Road, Edinburgh EH9 3JZ, United Kingdom.
The Journal of Chemical Physics
|April 10, 2014
Summary
This study presents an elastic rod model for semi-flexible polymers. The discrete model accurately reflects continuum behavior, validated by comparing correlation functions with simulations.
Area of Science:
- Polymer physics
- Computational modeling
Background:
- Semi-flexible polymers exhibit complex behavior governed by bending and twisting.
- Existing models may not fully capture continuum properties in simulations.
Purpose of the Study:
- To introduce and validate an elastic rod model for semi-flexible polymers.
- To bridge the gap between continuum theory and discrete simulations.
Main Methods:
- Reviewing continuum rod theory.
- Developing and analyzing a discretized rod model.
- Deriving correlation functions for bending and twisting.
- Comparing model results with numerical simulations.
Main Results:
- The discretized model correctly reproduces the continuum limit.
- Derived correlation functions match simulation data for bending and twisting.
- Two LAMMPS implementations of the model are detailed.
Conclusions:
- The presented elastic rod model is a valid and accurate representation of semi-flexible polymers.
- The model facilitates reliable simulations using molecular dynamics software.
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