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Updated: Oct 6, 2026

High-Contrast and Fast Photorheological Switching of a Twist-Bend Nematic Liquid Crystal
Published on: October 31, 2019
Mirror versus Inversion Symmetry Breaking in Mesogenic Dimers: NTB versus NF Phase
Małgorzata Bakiera1, Jakub Karcz1, Damian Pociecha2
1Faculty of Advanced Technology and Chemistry, Military University of Technology, Warsaw, Poland.
Abstract:
The recently discovered twist-bend nematic NTB and ferroelectric nematic NF phases are distinct examples of spontaneous symmetry breaking in liquid crystals. Here, we report the occurrence of both type nematic phases within the same homologous series of dimers consisting of two strongly dipolar mesogenic units linked by a flexible spacer. The NF phase, observed for dimers having spacer with even number of atoms, exhibits the strong polar order; in the NTB phase, observed for dimers with odd number of atoms in the spacer, short-pitch heliconical director structure develops.
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