螺旋形状の形態の共存は,星状のディスコティック・ヒドラゾーンが柱状に積み重なって存在する
Jie Shu1, Dmytro Dudenko, Morteza Esmaeili
1Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany.
Journal of the American Chemical Society
|July 9, 2013
まとめ
ディスコティックヒドラゾンの分子は,六角柱状の組織を持つ液晶 (LC) 段階を形成する. 複雑な結晶相は,アルコキシ鎖の長さに影響された螺旋状の堆積形態を明らかにし,有機電子学の可能性を示唆しています.
科学分野:
- マテリアルサイエンス 材料科学
- 有機化学 オーガニック・ケミストリー
- クリスタログラフィーです.
背景:
- ディスコティックヒドラゾンの分子は,分子内水素結合により,ユニークなディスコティック液晶 (LC) 段階を示します.
- これらの分子には,硬い核と柔軟な周辺アルコキシ鎖があり,その自己組み立てと相性に影響を与えます.
研究 の 目的:
- 異なるアルコキシ鎖長 (6 , 8 , 10 の炭素) のディスク性ヒドラゾン誘導体の熱otropic 行動と固体組織を調査する.
- 液体結晶と結晶の両相における分子包装と堆積形態の解明.
主な方法:
- 段階識別と構造分析のための二次元広角X線散射 (2DWAXS).
- 広角X線散射 (WAXS) と高度な固体核磁気共鳴 (SSNMR) を用いて,詳細な固体構造の決定を行う.
- 構造モデリングと分析をサポートする Ab initio 計算.
主要な成果:
- これら3つの化合物は,高温で非傾斜円盤を持つ六角柱状 (Colh) 液晶相を示した.
- 複雑な結晶相は,硬い柱と柔軟な横鎖を特徴とする6と10の炭素アルコキシ鎖を持つ化合物の25 °Cで観察されました.
- 異なる傾き/ピッチの角度を持つ共存する螺旋状柱状のスタッキング形態がモデル化され,アルコキシ鎖の長さに依存していることが示されました.
結論:
- アルコキシサイドチェーンの長さは,結晶柱状相におけるパッキングと傾斜/傾斜の角度に大きな影響を与える.
- 柱状液晶における観察された複雑な包装形態は希少であり,類似の有機系における複雑な構造の可能性を強調している.
- これらの発見は,有機電子アプリケーションの潜在的な材料として,ディスク性ヒドラゾン誘導体の有用性を示唆しています.
関連する概念動画
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