A coarse-graining approach to model molecular liquids for mesoscale problems

Effective modeling of molecular interactions is fundamental for understanding and simulating large-scale chemical and biochemical systems. Here, we introduce a novel coarse-graining strategy that employs the Lennard-Jones (LJ) potential to model solvent-solvent and solute-solvent interactions that control mesoscale behaviors. Our approach maintains the accuracy in capturing essential thermophysical properties such as densities and vapor pressures, while simplifying the representation of solvent molecules. By aggregating multiple solvent molecules into a single bead, our model offers a robust tool for studying solvation properties in systems where the collective behavior of solvents plays a crucial role. This approach enables effective computational studies across various mesoscale phenomena, including phase transitions in polymer blends, concentrated solutions of small organic molecules, and biological self-assembly. We demonstrate the robustness of our approach by simulating a saturated cholesterol-ethanol solution, exemplifying its power to tackle large-scale systems with precision and efficiency.