Extended Hybrid Particle-Field Approach for Simulating Polymeric Systems

We present a mesoscale simulation scheme developed based on the hybrid particle-field concept. It is acknowledged that particle- and field-based approaches enjoy distinct however complementary advantages. The former offers fully resolved microscopic details but suffers limited time/length scales when applied to systems of high densities and long-range interactions. The opposite can be generally said about field-based approach. In the proposed hybrid scheme, by decomposing interactions into subcomponents, suitable strategies can be prescribed to combines strengths of both approaches. Specifically, components producing fields of less fluctuations (e.g. pressure-like fields) are treated using a field-theoretic approach, and the ones producing strong correlations and fluctuations are retained in explicit particle forms. Evolution of fields can be simplified by adopting the saddle point values that are consistent with the instantaneous particle configuration, while conventional particle-based methods are used to sample particle coordinates. Fields and particles can be evolved at different rate, resulting a temporary decoupling that can be exploited for parallelized implementations. Several cases of applications will be discussed to illustrate the method’s performance and accuracy.