ABSTRACT
This chapter summarizes the coarse-graining (CG) approach that is called the Integral Equation Coarse-Grained (IECG) model. In most CG models, which are numerically solved, the step of running detailed atomistic simulations is necessary to be able to parameterize the model. Reducing the degrees of freedom comes with the consequence that some thermodynamic properties and the dynamical quantities are modified in a way that depend on the extent of CG. The coarse-grained models that have been proposed so far are mostly divided into two groups: bottom-up and top-down. The dynamics of the coarse-grained units is described by a Langevin equation where dissipation emerges from the procedure. The approach to the structure and dynamics of polymer liquids belongs to the group of bottom-up methods, where the pair distribution function is reproduced across variable levels of CG. The chapter concludes by presenting a coarse-grained approach to describe the fluctuating dynamics of folded proteins in dilute solutions.
