Hierarchical Deep Potential with Structure Constraints for Efficient Coarse-Grained Modeling.

Coarse-grained molecular dynamics is a powerful approach for simulating large-scale systems by reducing the number of degrees of freedom. Nonetheless, the development of accurate coarse-grained force fields remains challenging, particularly for complex systems, such as polymers. In this study, we introduce a novel framework, hierarchical deep potential with structure constraints (HDP-SC), designed to construct coarse-grained force fields for polymer materials. Our methodology integrates a prior energy term obtained through direct Boltzmann inversion with a deep neural network potential, which is trained using hierarchical bead environment descriptors. This framework facilitates the reproduction of structural distributions and the potential of mean force, thus enhancing the accuracy and efficiency of the coarse-grained model. We validate our approach using polystyrene systems, demonstrating that the HDP-SC model not only successfully reproduces the structural properties of these systems but also remains applicable at larger scales. Our findings underscore the promise of machine learning-based techniques in advancing the development of coarse-grained force fields for polymer materials.