Representing many-body effects in non-Markovian dissipative particle dynamics simulation

Coarse-grained molecular simulations based on non-Markovian dissipative particle dynamics can reproduce the dynamic properties of fluids, whereas they cannot reproduce the static properties with sufficient accuracy. This is because many-body effects are not considered. To overcome this drawback, we need an interaction model that considers neighborhood particle configurations near coarse-grained particles. In this study, as a method of modeling the conservative force term in the governing equation of non-Markovian dissipative particle dynamics, we define a density function to evaluate the particle configuration around coarse-grained particles and show the way to calculate the force acting on the coarse-grained particles based on this density function by conducting modal decomposition.