Water clusters in organic molecular crystals

The patterns of water clusters within the Cambridge Structural Database have been classified as discrete rings chains, infinite chains and tapes, and layer structures. Predominant patterns are found for discrete clusters 4-membered water rings, and in chains with a repeat unit of 4 waters. In tapes dominant patterns consist of 5-membered rings sharing one edge, and alternate 4,6-membered rings sharing one edge. If donor/acceptor groups are included from the organic molecules then the discrete water patterns transform into the dominant tape motifs.