Adaptive Resolution Molecular Dynamics Simulation: Changing the Degrees of Freedom on the Fly

TL;DR

This paper introduces an adaptive resolution technique for molecular dynamics that dynamically switches molecules between atomistic and coarse-grained representations, enabling efficient large-scale simulations with localized detail.

Contribution

The method allows molecules to change resolution levels on-the-fly during simulations, improving efficiency while maintaining statistical accuracy in multiscale MD systems.

Findings

Successfully tested on a liquid of tetrahedral molecules

Molecules switch resolution levels while preserving statistical properties

Enables large-scale simulations with localized atomistic detail

Abstract

We present a new adaptive resolution technique for efficient particle-based multiscale molecular dynamics (MD) simulations. The presented approach is tailor-made for molecular systems where atomistic resolution is required only in spatially localized domains whereas a lower mesoscopic level of detail is sufficient for the rest of the system. Our method allows an on-the-fly interchange between a given molecule's atomic and coarse-grained level of description, enabling us to reach large length and time scales while spatially retaining atomistic details of the system. The new approach is tested on a model system of a liquid of tetrahedral molecules. The simulation box is divided into two regions: one containing only atomistically resolved tetrahedral molecules, the other containing only one particle coarse-grained spherical molecules. The molecules can freely move between the two regions while changing their level of resolution accordingly. The coarse-grained and the atomistically resolved systems have the same statistical properties at the same physical conditions.