Curating Morphological Data: From the Compendium of P. von Groth to the Cambridge Structural Database

Abstract

Crystal morphology is a significant property in manufactured materials. Related to crystal structure and influenced by environment, manipulating crystal morphology is important for tailoring of product properties to performance and quality control standards. There is a shortage of high-quality morphological data for organic crystals. A largely untapped wealth of such data for over 2000 organic crystals is available in P. von Groth’s Chemische Kristallographie, a multivolume reference work, published in the early 20th century. The data are available online, but comparisons with more recent morphological and structural data are not straightforward. Here, the opportunity for a standardized, systematic approach linking Groth’s morphology data to crystal structures in the Cambridge Structural Database (CSD) is presented. A method is proposed based on matching unit cells to store morphological data in a standard format─the “morphology.cif”. This method is illustrated with four examples: benzophenone, glycine, urea, and α-lactose monohydrate, highlighting the particular challenges associated with polar morphologies. The steps necessary to implement such an approach systematically and hence to make maximum use of Groth’s work are discussed.