Slicing and Dicing: Optimal Coarse-Grained Representation to Preserve Molecular Kinetics

Area of Science:

• Computational chemistry
• Soft matter physics
• Molecular dynamics

Background:

• Molecular coarse-graining simplifies complex systems for efficient simulation.
• Current methods often rely on intuition for selecting key degrees of freedom.
• Accurate long-time dynamics are crucial for understanding soft matter behavior.

Purpose of the Study:

• To develop a coarse-graining scheme that preserves slow degrees of freedom.
• To accurately reproduce long-time dynamics by capturing rare-event transitions.
• To compare the proposed method with existing coarse-graining approaches.

Main Methods:

• A novel bottom-up coarse-graining scheme was proposed.
• The method focuses on preserving slow degrees of freedom.
• Tested on three systems of increasing complexity.

Main Results:

• The proposed scheme successfully preserves relevant slow degrees of freedom.
• It accurately recapitulates the slow time scales of the systems studied.
• Existing methods (information theory, structure-based) failed to capture these slow dynamics.

Conclusions:

• The new bottom-up coarse-graining method effectively captures rare-event transitions and long-time dynamics in soft matter.
• Preserving slow degrees of freedom is key for accurate coarse-grained simulations.
• This method offers an advantage over existing techniques for simulating soft matter systems.