Since in this DPD model dodecane is a 7-mer, the mean molar mass of a dodecane bead is M (C 12 H 26 )/7 ≈ 24.3 g mol -1 . Utilising Eq. ( ), this corresponds to a real mass density 3.27 × 24.3/0.108 ≈ 740 g L -1 , which is within 1.5% of the true value of 750 g L -1 . This is expected since the DPD parameters are tuned to reproduce liquid phase densities.