How Does the Surface Tension Depend on the Surface Area with Coarse-Grained Models?

We propose to investigate the size-effects on the surface tension calculated with coarse-grained (CG) models. We investigate different liquid–vapor (LV) and liquid–liquid (LL) interfaces with the MARTINI force field and original CG models designed for the dissipative particle dynamics (DPD) and multibody particle dynamics (MDPD) simulations. We also test a realistic CG potential developed for the DPD method to investigate the LV interface of n-pentane. Concerning the MARTINI force field, we observe a weak oscillatory effect of the interfacial tension with the surface area for the LV interfaces of n-octane and water. This weak dependence of the surface tension with the box dimension is also observed in the LL interface of n-octane-water (MARTINI, DPD) and in the LV interface of water with the MDPD model.