The structure of vinylene carbonate trimer given in 3B-69 trimer set is shown in Fig. , which was extracted from optimized molecular crystal. Independent gradient model based on Hirshfeld partition (IGMH) is a popular method of visually exhibiting interfragment interactions, IGMH isosurfaces are also appended to the trimer structure map to reveal all notable interactions between the three molecules. From the IGMH map one can find that the isosurfaces between the molecules are basically in green, indicating that the interactions can hardly be regarded as typical H-bonds. Indeed, C-H•••O type of interaction is known to be much weaker compared to common Hbonds. It is difficult to judge whether the interaction between the three molecules is electrostatics or dispersion dominated based on common knowledge. In order to find a definitive answer, we analyzed this system with sobEDAw, the result is ∆Eels = -14.53 kcal/mol, ∆Exrep = 15.14 kcal/mol, ∆Eorb = -4.30 kcal/mol and ∆Edisp = -9.77 kcal/mol, indicating that electrostatic effect plays a more important role than dispersion effect for the trimerization, while dispersion also contributes greatly. Furthermore, although the orbital interaction is relatively insignificant, it is not so small that can be ignored. All terms derived by sobEDAw for this system are in very reasonable ranges, which shows that this method is fully applicable to the interactions between more than two molecules.