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arXiv · 1708.08632

Heliconical smectic phases formed by achiral molecules

Jordan P. Abberley·Ross Killah·Rebecca Walker·John M. D. Storey·Corrie T. Imrie·Miroslaw Salamonczyk·Chenhui Zhu·Ewa Gorecka·Damian Pociecha
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Abstract

A series of asymmetric dimers with an odd number of atoms in the spacer were found to form different types of twisted structures despite being achiral. The formation of a variety of helical structures is accompanied by a gradual freezing of molecular rotation. The tight pitch heliconical nematic (NTB) phase and heliconical tilted smectic C (SmCTB) phase are formed. In the lowest temperature smectic phase, HexI, the twist is expressed through the formation of hierarchical structure: nano-scale helices and mesoscopic helical filaments. The short pitch helical structure in smectic phases is confirmed by resonant x-ray measurements.

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Jordan P. Abberley, Ross Killah, Rebecca Walker, John M. D. Storey, Corrie T. Imrie, Miroslaw Salamonczyk, Chenhui Zhu, Ewa Gorecka, Damian Pociecha. 2017-08-29. Heliconical smectic phases formed by achiral molecules. https://doi.org/10.1038/s41467-017-02626-6

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