複雑な多彩のタイルと,テトラフィリック液晶の重要な現象
Xiangbing Zeng1, Robert Kieffer, Benjamin Glettner
1Department of Materials Science and Engineering, University of Sheffield, Sheffield, UK.
Science (New York, N.Y.)
|March 12, 2011
まとめ
T形分子に相容れないサイドチェーンを加えると,複数の細胞の組成を持つ複雑な液晶蜂巣が生成されます. 磁気移行に類似した,相分離と混合ハネコブの相の間の可逆的な移行が観察されました.
科学分野:
- マテリアルサイエンス 材料科学
- ソフトマター物理学 ソフトマター物理学
- クリスタログラフィーです.
背景:
- T形の分子は,アロマティックなコアと柔軟なサイドチェーンを持つ液晶の蜂巣を形成します.
- これらの構造は,芳香的な細胞壁とサイドチェーンで満たされた内部を示しています.
- 以前の研究は,より単純な分子構造に焦点を当てていた.
研究 の 目的:
- T形液晶系に第二の互換性のないサイドチェーン (X形分子) を加えた結果の影響を調査する.
- 複雑なタイリングパターンの形成と細胞の組成の違いを探求する.
- 観測された熱可逆相変遷を特徴づける.
主な方法:
- T型およびX型分子の合成および特徴付け.
- 顕微鏡と熱的方法を用いた液晶相行動分析.
- ハネコブのパターンと細胞組成の構造分析.
主要な成果:
- X形分子を加えると,最大5つの異なる細胞組成 ("色") と多角形状の複雑なハネコブタイルが誘発されました.
- 互換性のないサイドチェーンの間の幾何学的な挫折は,クリーンフェーズ分離を妨げ,複雑性をもたらしました.
- 多色 (相分離) と単色 (混合) のハネコムフェーズ間の熱可逆の移行が観察されました.
結論:
- 液晶の相容れないサイドチェーンは,複雑な自己組み立て構造を生み出し,複雑性が生まれます.
- 観測された相変遷は,分子再方向化によって引き起こされる磁気系におけるキュリー変遷に類似しています.
- この研究は,柔らかい物質と挫折したシステムにおける自己組織化の理解を広げています.
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