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Measuring Magnetically-Tuned Ferroelectric Polarization in Liquid Crystals
Published on: August 15, 2018
熱otropic uniaxial and biaxial nematic and smectic phases in bent-core mesogens 曲った核メソゲンにおける熱otropic
Veena Prasad1, Shin-Woong Kang, K A Suresh
1Center for Liquid Crystal Research, P.O. Box 1329, Jalahalli, Bangalore 560 013, India.
Journal of the American Chemical Society
|December 8, 2005
まとめ
2つの新しいアゾ代用曲線核メソゲンは,熱心な液晶相を示しています. これらの材料は,単軸ネマティック,二軸ネマティック,および複数のスメクティック相の間の移行を示しており,これらはすべて2次元の移行であると確認されています.
科学分野:
- 材料科学 材料科学とは
- 有機化学 オーガニック・ケミストリー
- 凝縮物質物理学 凝縮物質物理学
背景:
- ベントコアメソゲンは,ユニークな性質を持つ液晶のクラスです.
- アゾで置換された化合物は,調節可能な電子および光学特性を提供します.
- 単一コンポーネントシステムにおける相変化の理解は,材料設計において極めて重要です.
研究 の 目的:
- 新型アゾ代用アキラル曲線核メソゲンを合成し,特徴づけること.
- これらの化合物によって表される熱型液晶相を調査するために.
- 熱および散乱技術を使用して相変化の順序を決定する.
主な方法:
- 2つのアゾ代用アキラル型ボンドコアメソゲンの合成.
- フェーズ識別のための光学極化顕微鏡.
- 構造分析のためのシンクロトロンX線散射.
- 熱行動の差分スキャニングカロメトリー.
主要な成果:
- 2つの標的メソゲン化合物の合成が成功しました.
- 熱otropic uniaxial nematic, biaxial nematic,および3つのスメクティックフェーズを識別する.
- 単軸ネマティックから二軸ネマティックへの二次相移行の確認.
- 二軸ネマティックからスメクティック・フェーズへ,そしてスメクティック・フェーズ間の二次移行の観測,最小の熱容量変化によって示される.
結論:
- 合成されたアゾー置換の曲った核メソゲンは,複雑な熱向性液晶の振る舞いを示しています.
- ネマティック-ネマティック,ネマティック-スメクティックを含む観測された相変遷は,主として二次である.
- これらの発見は,曲ったコアの液晶における構造-性質関係の基本的な理解に貢献します.
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