ディスコティックベンゾ[e][1,2,4]トリアジニルの置換依存磁気行動
Marcin Jasiński1, Jacek Szczytko2, Damian Pociecha3
1Faculty of Chemistry, University of Łódź , Tamka 12, 91-403 Łódź, Poland.
Journal of the American Chemical Society
|July 21, 2016
まとめ
ベンゾ[e][1,2,4]トリアジニルコアを持つ新しいディスクメソゲンは,ユニークな熱および磁気特性を示しています. これらの材料は,光誘導された穴の輸送を示し,先進的な電子アプリケーションにおけるその可能性を強調しています.
科学分野:
- 材料科学
- 有機化学
- 凝縮物質物理学
背景:
- ディスコ質の液晶は 柱状の構造に自己組織化することが知られている.
- ベンゾ[e][1,2,4]トリアジニルラジカルは,機能的なメソゲンを設計するためのユニークなコアを提供します.
- メソジェニックコアに代用物質を合わせると,その相性や電子特性に大きな影響を与える.
研究 の 目的:
- ベンゾ[e][1,2,4]トリアジニル基に基づく新しいディスク性メソゲンを合成し,特徴づけること.
- 柱状六角形 (Colh) 段階,熱膨張,磁気相互作用に対するN(1) 置換物の影響を調査する.
- コルヒ相におけるこれらのメソゲンの光誘導電荷輸送特性を評価する.
主な方法:
- ベンゾ[e][1,2,4]トリアジニル基のディスク性メソゲンの合成,異なるN(1) 置換剤を用いる.
- 分散スキャニングカロメトリー (DSC) と極光光学顕微鏡 (POM) で,相変化と熱膨張を研究する.
- 磁気相互作用を検出するための磁気感受性測定
- 飛行時間 (TOF) または類似の技術を使用してフォト誘導の穴輸送測定.
主要な成果:
- ディスコティックメソゲンは,80°C以下でコルヒ相を示す.
- N(1) -フェニル (1a) と1-PhF-m (1b) 誘導体は,熱膨張と反鉄磁気相互作用を呈する.
- 1c (X=O) と1d (X=S) のC12H25X) 3C6H2) の微分は負の熱膨張を示している.
- 1c (J/kB = +4. 76 K) で観測された弱い鉄磁気相互作用.
- 化合物1aと1cは,コルフ相における光誘導の穴輸送 (μ ≈ 1.3 × 10(-3) cm(2) V(-1) s(-1)) を示している.
結論:
- N(1) 置換剤は,ベンゾ[e][1,2,4]トリアジニルディスク性メソゲンの分子組織,熱膨張,磁気行動を決定的に制御する.
- 大量のアルコシ/チオアルコシサイドチェーンを持つ誘導体で観測された負の熱膨張.
- コルヒ相における光誘導孔輸送の存在は,有機電子学の潜在的な応用を示唆する.
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