sentence: As for Cluster 5 , it does not resemble any of the canonical CGs at all , except maybe a highly distorted Pyv , where it has three ligands on the same plane very close to each other , and the fourth ligand – zinc bond perpendicular to that plane.Now , if we use k ‐ means on both normal and compressed group together instead of separately , stability tests show that k = 10 and k = 14 are the potential optimal clustering numbers ( Supporting Information Fig. S3 ) .