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Updated: Feb 14, 2026
High-Contrast and Fast Photorheological Switching of a Twist-Bend Nematic Liquid Crystal
Published on: October 31, 2019
Control of Photomechanical Crystal Twisting by Illumination Direction
Daichi Kitagawa1, Hajime Tsujioka1, Fei Tong2
1Department of Applied Chemistry, Graduate School of Engineering , Osaka City University , 3-3-138 Sugimoto , Sumiyoshi-ku, Osaka 558-8585 , Japan.
Abstract:
Photomechanical molecular crystals have been investigated as mesoscopic photoactuators. Here, we report how the photomechanical twisting of 1,2-bis(2-methyl-5-phenyl-3-thienyl)perfluorocyclopentene (1a) crystals depends on illumination direction. The ribbon-like crystal of 1a could be successfully prepared by a sublimation method. The ribbon crystal exhibited reversible photomechanical crystal twisting upon alternating irradiation with ultraviolet (UV) and visible light. Moreover, changing the UV illumination direction with respect to the crystal resulted in different twisting modes, ranging from helicoid to cylindrical. Control of photomechanical crystal deformation by illumination direction provides a convenient and useful way to generate a variety of photomechanical motions from a single crystal.
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