Towards the use of realistic coarse-grained models

The coarse-grained (CG) models have been developed to study complex systems that relax over times that are longer than a microsecond. In this CG models, the particle may correspond to many atoms or molecules. In the past,... [ view full abstract ]

The coarse-grained (CG) models have been developed to study complex systems that relax over times that are longer than a microsecond. In this CG models, the particle may correspond to many atoms or molecules. In the past, these CG potentials have been extensively applied to simulate generic polymer melts. More recently, it is possible to obtain realistic CG models by using different approaches. The top-down approach derives the parameters of the CG force field from macroscopic properties (compressibility, surface tension,..) whereas the bottom-up approach uses an integration over the atomistic degrees of freedom to develop the CG potential.

A number of CG force fields have been developed by using different degrees of coarse-graining. Among these force fields, we note the MARTINI model, the SAFT-g that are used with modified Lennard-Jones potentials. It is also possible to use these CG models with mesoscopic methods such as dissipative particle dynamics or Brownian dynamics methods.

We propose here to discuss the performance of these CG models in the prediction of the interface tension of liquid-vapour, liquid-liquid and oil-water-surfactants interfaces. We extend the discussion to the adsorption of polymer chains onto silica surfaces. We will show that these CG models are able to capture what occurs at the interface in terms of specific structural arrangements.