(470g) Effects of Coarse-Graining on the Behavior of Self-Assembling Systems

In many self-assembling systems of practical interest, balancing multiple time and length scales is imperative to controlling the size, composition, and stability of the structures that are formed. Self-assembly of non-equilibrium structures, for example, is heavily influenced by the rate at which molecular processes occur relative to one another. We have used DPD simulations of chain molecules in solvent to investigate the effects of coarse-graining on the static and dynamic properties of the system. In particular, we have focused on the scaling of the radius of gyration, center-of-mass diffusion coefficient, and head-to-tail distance of the chain molecules with chain length in DPD simulations. We have found that coarse-graining both solvent particles and chain particles leads to inconsistent changes in the length-dependent and time-dependent properties of the chains. This indicates that the mapping of non-dimensional simulation parameters to dimensional, real parameters is non-trivial. In addition, we have employed Gibbs ensemble Monte Carlo simulations to investigate the effect of coarse-graining on the phase behavior of polymer-solvent systems interacting via DPD potentials. We seek to develop a consistent way of interpreting the changes in thermodynamic and transport properties that arise due to coarse-graining.