Adaptive multiscale molecular dynamics of macromolecular fluids.

Until now, adaptive atomistic-coarse-grain (A/CG) molecular dynamics simulations have had very limited applicability because the on-the-fly CG → A transformation is problematic for all but those molecules whose CG representation consists of a single particle. Here, we solve this problem by combining a transitional healing region with a rotational dynamics of rigid atomistic fragments in the CG region. Error control is obtained by analysis of the A ↔ CG energy flow. We illustrate the method with adaptive multiscale simulations of liquid hexane and of a dilute polymer solution in a theta solvent.