Data-driven coarse-grained modeling of polymers in solution with structural and dynamic properties conserved.
Shu Wang1, Zhan Ma1, Wenxiao Pan1
1Department of Mechanical Engineering, University of Wisconsin-Madison, Madison, WI 53706, USA. wpan9@wisc.edu.
Soft Matter
|August 14, 2020
Summary
We developed a data-driven coarse-grained (CG) model for polymers in solution that accurately captures dynamic and structural properties. This advanced CG modeling conserves essential characteristics of atomistic systems.
Area of Science:
- Computational chemistry and materials science
- Polymer physics and simulations
Background:
- Atomistic simulations provide detailed polymer behavior but are computationally expensive.
- Coarse-grained (CG) modeling simplifies systems but often struggles to conserve dynamic and structural properties.
- The generalized Langevin equation (GLE) framework offers a path for accurate CG modeling.
Purpose of the Study:
- To develop a data-driven coarse-grained (CG) modeling approach for polymers in solution.
- To ensure the CG model conserves both dynamic and structural properties of the atomistic system.
- To enhance computational efficiency in polymer simulations.
Main Methods:
- Utilized the generalized Langevin equation (GLE) framework.
- Employed a two-stage Gaussian process-based Bayesian optimization to infer the non-Markovian memory kernel from velocity autocorrelation function (VACF) data.
- Developed an active learning method to identify hydrodynamic scaling in VACF and memory kernel, accelerating kernel inference.
- Compared deep learning and iterative Boltzmann inversion for constructing the CG potential.
- Mapped the GLE onto an extended Markovian process for computational efficiency.
Main Results:
- The proposed CG modeling robustly and accurately reproduced dynamic and structural properties of polymers in solution.
- Demonstrated conservation of key properties compared to reference atomistic simulations.
- Assessed accuracy and computational efficiency using a model star-polymer solution system across various concentrations.
Conclusions:
- The developed data-driven CG modeling approach effectively captures polymer dynamics and structures in solution.
- The method offers a computationally efficient alternative to atomistic simulations while maintaining high accuracy.
- This approach provides a powerful tool for studying complex polymer systems.
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