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arXiv · 1308.3526

Twist-bend heliconical chiral nematic liquid crystal phase of an achiral rigid bent-core mesogen

Dong Chen·Michi Nakata·Renfan Shao·Michael R. Tuchband·Min Shuai·Ute Baumeister·Wolfgang Weissflog·David M. Walba·Matthew A. Glaser·Joseph E. Maclennan·Noel A. Clark
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Abstract

The chiral, heliconical (twist-bend) nematic ground state is reported in an achiral, rigid, bent-core mesogen (UD68). Similar to the nematic twist-bend (NTB) phase observed in bent molecular dimers, the NTB phase of UD68 forms macroscopic, smectic-like focal-conic textures and exhibits nanoscale, periodic modulation with no associated modulation of the electron density, i.e., without a detectable lamellar x-ray reflection peak. The NTB helical pitch is pTB ~ 14 nm. When an electric field is applied normal to the helix axis, a weak electroclinic effect is observed, revealing 50 um-scale left- and right-handed domains in a chiral conglomerate.

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Dong Chen, Michi Nakata, Renfan Shao, Michael R. Tuchband, Min Shuai, Ute Baumeister, Wolfgang Weissflog, David M. Walba, Matthew A. Glaser, Joseph E. Maclennan, Noel A. Clark. 2013-08-16. Twist-bend heliconical chiral nematic liquid crystal phase of an achiral rigid bent-core mesogen. https://doi.org/10.1103/physreve.89.022506

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