Ferroelectrically Switching Helical Columnar Assembly Comprising Cisoid Conformers of a 1,2,3‐Triazole‐based Liquid Crystal

1,2,3‐Triazole (known as a product of click chemistry) with a high dipole moment can be a useful polar motif for ferroelectric columnar liquid crystalline (LC) materials, though it has not been used to date. Herein, we report the helical assembly and ferroelectric switching properties of a columnar liquid crystal comprising a naphthalene core and 1,2,3‐triazolyl linkages. The molecule assembles into a double‐stranded helical columnar LC structure (Colhel). The X‐ray simulations of cisoid and transoid columnar models suggest that the helical assembly comprises cisoid conformers with a non‐zero dipole moment. The helical columns in the Colhel phase are aligned homeotropically under an electric field. The ferroelectric switching of the axial polarization can be observed in the temperature range of 105‐115 oC in the Colhel phase, wherein the triazolyl hydrogen bonding along the columnar axis is weakened. The ferroelectric switching event is attributed to the rotation of the polar triazolyl units in response to the electric field.

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