The multiscale coarse-graining method. IX. A general method for construction of three body coarse-grained force...

Area of Science:

• Computational Chemistry
• Materials Science
• Statistical Mechanics

Background:

• The multiscale coarse-graining (MS-CG) method constructs coarse-grained (CG) models from atomistic simulations.
• Current MS-CG applications often use pairwise interactions, which can be insufficient for certain systems.
• A more general approach is needed to improve the accuracy of CG potentials.

Purpose of the Study:

• To develop a systematic method for incorporating three-body terms alongside two-body terms in MS-CG potentials.
• To create a more general framework that does not impose restrictive functional forms on three-body potentials.
• To enhance the accuracy of CG models by including higher-order interactions.

Main Methods:

• Utilized hierarchical multiresolution functions, analogous to wavelets, for flexible basis function expansions.
• Developed a variational approach to solve the problem, incorporating both two- and three-body basis functions.
• Employed a numerical technique for automatic selection of basis functions from a large initial set.

Main Results:

• Successfully applied the method to a two-component Lennard-Jones solution and a one-site SPC/E water model.
• Demonstrated that including three-body terms significantly improves the accuracy of CG potentials.
• Showcased the method's generality and flexibility in representing complex interactions.

Conclusions:

• The proposed systematic inclusion of three-body terms enhances the accuracy of MS-CG potentials.
• This advancement leads to more reliable coarse-grained simulations.
• The method provides a more robust framework for developing accurate CG models across diverse systems.