In this work, MD simulations, in combination with Well Tempered Metadynamics (WTmetaD), have been used to study the formation of a surface vacancy from a defect-free crystal facet (state A) to an adsorbed on the crystal surface state (state B) as shown in Fig. . Simulations were performed for each morphologically dominant crystal facet of ibuprofen, namely the {100}, the {002} and the {011} faces, for ten different solventswater, 1-butanol, toluene, cyclohexanone, cyclohexane, acetonitrile, trichloromethane, methanol, ethyl acetate, ethanol. The {110} is occasionally also considered as a morhphologically dominant crystal face, but was excluded from the analysis in this study due to its generally rough nature and tendency for spontaneous surface roughening and dissolution, indicating a comparably lower barrier to the process of interest and therefore, lower morphological importance. 11,