Crystals of Benzamide, the First Polymorphous Molecular Compound, Are Helicoidal

Alexander G Shtukenberg; Ran Drori; Elena V Sturm; Netta Vidavsky; Asaf Haddad; Jason Zheng; Lara A Estroff; Haim Weissman; Sharon G Wolf; Eyal Shimoni; Chao Li; Noalle Fellah; Efi Efrati; Bart Kahr

doi:10.1002/anie.202005738

Crystals of Benzamide, the First Polymorphous Molecular Compound, Are Helicoidal

Angew Chem Int Ed Engl. 2020 Aug 17;59(34):14593-14601. doi: 10.1002/anie.202005738. Epub 2020 Jul 6.

Authors

Alexander G Shtukenberg¹, Ran Drori², Elena V Sturm³, Netta Vidavsky⁴, Asaf Haddad⁵, Jason Zheng¹, Lara A Estroff^{6

7}, Haim Weissman⁸, Sharon G Wolf⁹, Eyal Shimoni⁹, Chao Li¹, Noalle Fellah¹, Efi Efrati⁵, Bart Kahr¹

Affiliations

¹ Department of Chemistry and Molecular Design Institute, New York University, 100 Washington Square East, New York, NY, 10003, USA.
² Department of Chemistry and Biochemistry, Yeshiva University, 245 Lexington Avenue, New York, NY, 10016, USA.
³ Department of Chemistry, University of Konstanz, Universitätsstraße 10, 78457, Konstanz, Germany.
⁴ Department of Chemical Engineering, Ben-Gurion University of the Negev, 84105, Beer Sheva, Israel.
⁵ Department of Physics of Complex Systems, Faculty of Physics, Weizmann Institute of Science, 234 Hertzel Street, PO Box 26, 7610001, Rehovot, Israel.
⁶ Department of Materials Science and Engineering, Cornell University, 210 Bard Hall, Ithaca, NY, 14850, USA.
⁷ Kavli Institute at Cornell for Nanoscale Science, Cornell University, 420 Physical Sciences Building, Ithaca, NY, 14853, USA.
⁸ Department of Organic Chemistry, Faculty of Chemistry, Weizmann Institute of Science, 234 Hertzel Street, PO Box 26, 7610001, Rehovot, Israel.
⁹ Department of Chemical Research Support, Faculty of Chemistry, Weizmann Institute of Science, 234 Hertzel Street, PO Box 26, 7610001, Rehovot, Israel.

PMID: 32472617
DOI: 10.1002/anie.202005738

Abstract

The growth of spontaneously twisted crystals is a common but poorly understood phenomenon. An analysis of the formation of twisted crystals of a metastable benzamide polymorph (form II) crystallizing from highly supersaturated aqueous and ethanol solutions is given here. Benzamide, the first polymorphic molecular crystal reported (1832), would have been the first helicoidal crystal observed had the original authors undertaken an analysis by light microscopy. Polymorphism and twisting frequently concur as they are both associated with high thermodynamic driving forces for crystallization. Optical and electron microscopies as well as electron and powder X-ray diffraction reveal a complex lamellar structure of benzamide form II needle-like crystals. The internal stress produced by the overgrowth of lamellae is shown to be able to create a twist moment that is responsible for the observed non-classical morphologies.

Keywords: benzamide; disorder; internal stress; polymorphism; twisted crystals.

Publication types

Research Support, U.S. Gov't, Non-P.H.S.
Research Support, Non-U.S. Gov't