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. 2020 Oct 19;3(1):142.
doi: 10.1038/s42004-020-00388-9.

Open questions in organic crystal polymorphism

Aurora J Cruz-Cabeza  1 , Neil Feeder  2 , Roger J Davey  3
Affiliations

Open questions in organic crystal polymorphism

Aurora J Cruz-Cabeza et al. Commun Chem. .

Abstract

Polymorphs, crystals with different structure and properties but the same molecular composition, arise from the subtle interplay between thermodynamics and kinetics during crystallisation. In this opinion piece, the authors review the latest developments in the field of polymorphism and discuss standing open questions.

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Conflict of interest statement

The authors declare no competing interests.

Figures

Fig. 1
Fig. 1. Supramolecular assembly evolution of p-aminobenzoic acid (pABA) from a single molecule into crystallites of two different polymorphs.
The assembly occurs via two different routes (pink and blue) as a consequence of two different types of crystallisation conditions (X and Y), which leads to different early assembly, polymorphic structure, crystal shapes and material properties.
Fig. 2
Fig. 2. Similar compounds can behave very differently when it comes to polymorphism.
Molecular structure, Cambridge Structural Database six-letter family refcode and number of polymorphs for anthracene, phenazine, 9,10-anthraquinone and acridine.
See this image and copyright information in PMC

References

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    1. Schur E, et al. The (current) acridine solid form landscape: eight polymorphs and a hydrate. Cryst. Growth Des. 2019;19:4884–4893. doi: 10.1021/acs.cgd.9b00557. - DOI
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