The Theory of Ultra-Coarse-Graining. 2. Numerical Implementation

Area of Science:

• Computational Chemistry
• Molecular Modeling
• Statistical Mechanics

Background:

• Coarse-graining (CG) techniques are vital for modeling complex macromolecular systems.
• Existing CG models often assume sub-resolution details average out, limiting resolution and applications.
• There is a need for CG methods that can incorporate internal molecular dynamics.

Purpose of the Study:

• To introduce and discuss the Ultra-Coarse-Graining (UCG) methodology.
• To detail the numerical implementation of UCG, focusing on state transitions within CG sites.
• To demonstrate UCG's capability in modeling molecular liquids with high resolution.

Main Methods:

• Development of the Ultra-Coarse-Graining (UCG) methodology.
• Numerical implementation of UCG, including a novel mechanism for intra-site conformational transitions.
• Application of UCG to model 1,2-dichloroethane at a single-site-per-molecule resolution.

Main Results:

• The UCG methodology allows for model construction at any desired resolution.
• UCG successfully accounts for discrete conformational changes within CG sites, modulating interactions.
• The UCG model accurately reproduced the multiconfigurational behavior of 1,2-dichloroethane using single CG sites per molecule.

Conclusions:

• UCG offers a powerful approach to coarse-grained modeling, overcoming limitations of traditional methods.
• The ability to include state transitions within CG sites enhances model accuracy and applicability.
• UCG is applicable to diverse molecular liquids and macromolecular systems with timescale separation.