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arXiv · 1811.12331

Chiral shape fluctuations and the origin of chirality in cholesteric phases of DNA origamis

Maxime M. C. Tortora·Garima Mishra·Domen Presern·Jonathan P. K. Doye
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Abstract

Lyotropic cholesteric liquid crystal phases are ubiquitously observed in biological and synthetic polymer solutions, characterized by a complex interplay between thermal fluctuations, entropic and enthalpic forces. The elucidation of the link between microscopic features and macroscopic chiral structure, and of the relative roles of these competing contributions on phase organization, remains a topical issue. Here we provide theoretical evidence of a novel mechanism of chirality amplification in lyotropic liquid crystals, whereby phase chirality is governed by fluctuation-stabilized helical deformations in the conformations of their constituent molecules. Our results compare favorably to recent experimental studies of DNA origami assemblies and demonstrate the influence of intra-molecular mechanics on chiral supra-molecular order, with potential implications for a broad class of experimentally-relevant colloidal systems.

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Maxime M. C. Tortora, Garima Mishra, Domen Presern, Jonathan P. K. Doye. 2018-11-29. Chiral shape fluctuations and the origin of chirality in cholesteric phases of DNA origamis. https://doi.org/10.1126/sciadv.aaw8331

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