(621e) Molecular Dynamics of Continuous Chains: A Reduced-Order Simulation Model

We present a novel, computationally reduced method for the molecular dynamics simulation of entangled polymer systems. The polymer chains are modeled as continuous Gaussian chains, which may interact via interchain and intrachain excluded volume interactions. Our algorithm is based on the application of the molecular dynamics simulation method to the pseudospectral representation of the Fourier modes of the chains. We demonstrate that the computational complexity of our method per time step per chain is independent of chain length, thereby enabling a reduction in computational time in comparison to conventional molecular dynamics simulations applied to the bead-spring model, which require computational time of linear order in the chain length per time step per chain. We further show that our model polymer system can exhibit either semiflexible or flexible behavior, depending on whether intrachain excluded volume interactions are present or absent, respectively. Consequently, our model can accommodate a wide variety of polymer systems, ranging from semiflexible biopolymer networks to flexible polymer melts.