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arXiv · 2607.17989

Mirror vs. inversion symmetry breaking in mesogenic dimers: NTB vs. NF phase

Małgorzata Bakiera·Jakub Karcz·Damian Pociecha·Katarzyna Kwiatkowska·Mateusz Pawlak·Przemysław Kula·Ewa Gorecka
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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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Małgorzata Bakiera, Jakub Karcz, Damian Pociecha, Katarzyna Kwiatkowska, Mateusz Pawlak, Przemysław Kula, Ewa Gorecka. 2026-07-20. Mirror vs. inversion symmetry breaking in mesogenic dimers: NTB vs. NF phase. https://arxiv.org/abs/2607.17989

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