Ferroelectrically Switching Helical Columnar Assembly Comprising Cisoid Conformers of a 1,2,3-Triazole-based Liquid Crystal.
Manh Linh NguyenJaeduk ByunSuwoong KimJune Won HyunKahyun HurTae Joo ShinByoung-Ki ChoPublished in: Angewandte Chemie (International ed. in English) (2019)
The 1,2,3-triazole molecule, which is a product of click chemistry, possesses a high dipole moment and can be a useful polar motif for ferroelectric columnar liquid crystal (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 °C in the Colhel phase, wherein the triazolyl hydrogen bonding along the column axis is weakened. The ferroelectric switching event is attributed to the rotation of the polar triazolyl units in response to the electric field.