Monte Carlo Simulation and Machine Learning-Assisted Scattering Analysis of Mechanically Driven Polymers

ORAL

Abstract

We develop off-lattice Markov Chain Monte Carlo simulations and a Machine Learning Inversion method to analyze the behavior of semiflexible polymers under external forces. We model the polymer as a chain of fixed-length bonds subjected to bending energy, with configurations updated through adaptive non-local Monte Carlo moves. This enables accurate predictions of polymer response under uniaxial stretching and steady shear, overcoming the orientational bias of on-lattice models. The polymer conformation is captured by the scattering function. We apply a Machine Learning inversion method to extract key energy and conformation parameters from the scattering function. Using a dataset generated from Monte Carlo simulations, we train a Gaussian Process Regressor to successfully recover the bending modulus, stretching and shear forces, as well as end-to-end distance, radius of gyration, and the off-diagonal component of the gyration tensor. Our combined approach enhances precision in studying polymer behavior, offering insights into scattering functions and polymer conformation.

*This research was performed at the Spallation Neutron Source and the Center for Nanophase Materials Sciences, which are DOE Office of Science User Facilities operated by Oak Ridge National Laboratory. This research was sponsored by the Laboratory Directed Research and Development Program of Oak Ridge National Laboratory, managed by UT-Battelle, LLC, for the U. S. Department of Energy. The ML aspects were supported by by the U.S. Department of Energy Office of Science, Office of Basic Energy Sciences Data, Artificial Intelligence and Machine Learning at DOE Scientific User Facilities Program under Award Number 34532. Monte Carlo simulations and computations used resources of the Oak Ridge Leadership Computing Facility, which is supported by the DOE Office of Science under Contract DE-AC05-00OR22725.

Publication: Off-Lattice Markov Chain Monte Carlo Simulations of Mechanically Driven Polymers (https://doi.org/10.48550/arXiv.2409.15223)
Machine Learning Inversion from Scattering for Mechanically Driven Polymers (https://doi.org/10.48550/arXiv.2410.05574)

Presenters

  • Lijie Ding

    • Oak Ridge National Laboratory

Authors

  • Lijie Ding

    • Oak Ridge National Laboratory
  • Chi-Huan Tung

    • Oak Ridge National Laboratory
  • Bobby G Sumpter

    • Oak Ridge National Laboratory
  • Wei-Ren Chen

    • Oak Ridge National Lab
  • Changwoo Do

    • Oak Ridge National Lab
    • Oak Ridge National Laboratory