Development of Coarse-Grained Force Field by Combining Multilinear Interpolation Technique and Simplex Algorithm.

Area of Science:

• Computational chemistry
• Materials science
• Chemical physics

Background:

• Developing accurate coarse-grained (CG) molecular dynamics force fields (FFs) is crucial for simulating complex systems.
• Traditional FF parameterization is computationally intensive, limiting rapid development.
• Combining experimental and simulation data requires efficient and transferable FFs.

Purpose of the Study:

• To present an efficient optimization protocol for developing CG molecular dynamics FFs.
• To construct a new CG FF for water and n-alkanes using experimental properties as benchmarks.
• To validate the FF's accuracy and transferability for pure liquids and mixtures.

Main Methods:

• Developed an efficient optimization protocol combining multilinear interpolation and the simplex algorithm.
• Utilized a piecewise Morse function to model nonbonded interactions in the CG FF.
• Applied the optimized FF to predict structural and thermodynamic properties of water and alkane liquids.

Main Results:

• The new CG FF demonstrated a balance between efficiency, accuracy, and transferability.
• Successfully reproduced structural and thermodynamic properties of pure water and alkane liquids.
• Accurately predicted phase separation, interfacial tension, hydration free energy, and microemulsion formation in water/oil mixtures.

Conclusions:

• The developed CG FF offers an efficient and accurate approach for molecular dynamics simulations.
• The optimized Morse potential effectively describes interactions between water and n-alkanes.
• This method facilitates the combination of experimental and simulation data for complex mixtures.