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Published on: October 31, 2019
Pretransitional layer contraction at the chiral smectic A-to-chiral smectic C phase transition of a chiral nitroxide
Yoshiaki Uchida1, Katsuaki Suzuki, Rui Tamura
1Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama-cho, Toyonaka, Osaka 560-8531, Japan. yuchida@cheng.es.osaka-u.ac.jp
Abstract:
We have designed and synthesized a new chiral paramagnetic liquid crystalline compound with a nitroxide radical moiety showing chiral smectic A (SmA*) and C (SmC*) phases. This compound shows pretransitional layer contraction prior to the SmA*-to-SmC* phase transition in the cooling run. Electron paramagnetic resonance spectroscopy, X-ray diffraction analysis, and polarized optical microscopy reveal that a temperature-dependent conformational change is responsible for the pretransitional layer contraction.
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