Evaluation of Coarse Grained Potential

Coarse-Grained Molecular Dynamics (CGMD) simulations of polybutadiene were performed. Using J-OCTA’s functionality, bond length, angle, and dihedral distributions between Coarse-Grained units were evaluated from Full-Atomistic Molecular Dynamics (FAMD) results to determine Coarse-Grained potentials. Bulk polymer structures were then evaluated, and reverse mapping was used to reconstruct Full-Atomistic structures.

Use Cases Highlights

Estimation of Coarse-Grained potentials
Evaluation of polymer structure in the bulk state
Construction of Full-Atomistic models via reverse mapping

Evaluation of Coarse-Grained potentials

Coarse-Grained Molecular Dynamics (CGMD) simulations of an isolated polybutadiene chain in vacuum using Coarse-Grained potentials obtained with J-OCTA are shown. Bond length, bond angle, and dihedral angle distributions are compared with those from Full-Atomistic Molecular Dynamics (FAMD), showing good agreement.

Evaluation of Coarse-Grained potentials

Evaluation of bulk polymer structures

NPT ensemble calculations for bulk states with varying polymerization degree N confirmed that the ratio of the radius of gyration to the square of the end-to-end distance approaches 6 as N increases, a characteristic of ideal polymer chains.

Structure of bulk polymer chains (radius of gyration and end-to-end distance)

Reverse mapping to a Full-Atomistic model

Using reverse mapping, monomer structures of the Full-Atomistic model were placed so that the bond axes matched, based on the relaxation calculation results of Coarse-Grained Molecular Dynamics (CGMD), creating a more relaxed Full-Atomistic Molecular Dynamics (FAMD) structure.