Molecular modeling of crystal morphology of ginsenoside compound K solvates and its crystal habit modification by solvent molecules

The crystal growth morphology of ginsenoside compound K solvates was predicted by molecular modeling, and the solvent effect on crystal habits was considered to obtain a more accurate predicted result. The single crystal structures of two solvates of ginsenoside compound K (acetone–water solvate, monohydrate) were obtained by single crystal X-ray diffraction. On the basis of single crystal data, the crystal habits of the solvates were predicted by Bravais–Friedel–Donnay–Harker (BFDH) model and Attachment Energy (AE) model. From the image of scanning electron microscopy (SEM), it was shown that the AE model fits much better than the BFDH model. In addition, considering the interaction energy between solvent molecules and crystal faces (Eint), the AE model was modified. With the modification of AE model, the predicted crystal habits were in good agreement with our experimental results. ► Crystal habit of ginsenoside compound K solvates was predicted by two models. ► The single crystal structures of two solvates of ginsenoside compound K were obtained. ► Predicted crystal habits were modified with the consideration of solvent effect.