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. 2020 Jan 1;7(Pt 1):5-9.
doi: 10.1107/S2052252519016105.

Polymorph evolution during crystal growth studied by 3D electron diffraction

Edward T Broadhurst  1 , Hongyi Xu  2 , Max T B Clabbers  2 , Molly Lightowler  2 , Fabio Nudelman  1 , Xiaodong Zou  2 , Simon Parsons  1
Affiliations

Polymorph evolution during crystal growth studied by 3D electron diffraction

Edward T Broadhurst et al. IUCrJ. .

Abstract

3D electron diffraction (3DED) has been used to follow polymorph evolution in the crystallization of glycine from aqueous solution. The three polymorphs of glycine which exist under ambient conditions follow the stability order β < α < γ. The least stable β polymorph forms within the first 3 min, but this begins to yield the α-form after only 1 min more. Both structures could be determined from continuous rotation electron diffraction data collected in less than 20 s on crystals of thickness ∼100 nm. Even though the γ-form is thermodynamically the most stable polymorph, kinetics favour the α-form, which dominates after prolonged standing. In the same sample, some β and one crystallite of the γ polymorph were also observed.

Keywords: 3DED; cryoTEM; crystallization; electron diffraction; glycine; polymorphism.

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Figures

Figure 1
Figure 1
CryoTEM images (a), (c) and (e) with corresponding diffraction patterns (b), (d) and (f). (a) and (b) show β-glycine after 3 min of crystallization; (c) and (d) show α-glycine after 4 min; and (e) and (f) show γ-glycine after crystallization on a glass slide. The black circles on (a), (c) and (e) indicate the part of the crystal where the diffraction pattern was measured. Indexed reflections are shown on the diffraction patterns (b), (d) and (f). Scale bars: 3 µm. 2D slices from the 3D reciprocal lattices of selected datasets are provided in the supporting information.
Figure 2
Figure 2
Crystal structures of (a) β-glycine, (b) α-glycine and (c) γ-glycine determined from 3DED data. All views are along the c axis. NH⋯O hydrogen bonds are shown as dotted lines. C – grey, O – black, N and H – white.
See this image and copyright information in PMC

References

    1. Andrusenko, I., Hamilton, V., Mugnaioli, E., Lanza, A., Hall, C., Potticary, J., Hall, S. R. & Gemmi, M. (2019). Angew. Chem. Int. Ed. 58, 10919–10922. - PubMed
    1. Bauer, J., Spanton, S., Henry, R., Quick, J., Dziki, W., Porter, W. & Morris, J. (2001). Pharm. Res. 18, 859–866. - PubMed
    1. Bernal, J. D. (1931). Z. Krist. 78, 363–369.
    1. Bernstein, J. (2010). Polymorphism in Molecular Crystals. Oxford University Press.
    1. Boldyreva, E. V., Drebushchak, V. A., Drebushchak, T. N., Paukov, I. E., Kovalevskaya, Y. A. & Shutova, E. S. (2003). J. Therm. Anal. Calorim. 73, 409–418.