Another illustrative example is the work of Kamath et al. on azeotropes of acetone/methanol and chloroform/methanol systems, where force fields that accurately reproduced the pure components of these systems were unable to predict the azeotropic phase behavior until reparameterized against simulation of those mixture systems. In addition, Statistical Associating Fluid Theory (SAFT) can be used to predict the behavior of mixtures; in particular, the SAFT-group contribution method has been used by Mueller and coworkers to produce coarse-grained force fields for molecular fluid simulations and accurately predict the behavior of mixtures . Another important example is the Kirkwood-Buff Force Field (KBFF) of Smith and coworkers, which aims to achieve better treatment of solute-solvent interactions by capturing the concentration-dependent activities via Kirkwood-Buff theory . Using Kirkwood-Buff integrals, the macroscopic activity can be related to microscopic solution structures obtained from simulation. Their efforts have focused on adjusting charge parameters, along with some LJ parameters, to match Kirkwood-Buff integral values and better capture solute-solvent interactions. This method has been used to parameterize a wide range of systems, from simple systems to a complete protein and peptide force field .