3D超分子秩序を増加させ,分子秩序を減少させる. デンドロン化非塩素化およびテトラ塩素化ペリレンビシミドの螺旋組の比較研究
Benjamin E Partridge, Pawaret Leowanawat, Emad Aqad
1‡Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6396, United States.
Journal of the American Chemical Society
|April 2, 2015
まとめ
研究者らは,デンドロンを使った新型四塩化ペリレンビシミド (Cl4PBI) 分子を開発し,超分子組成で強化された3D結晶の秩序を達成した. これは,分析とアプリケーションのためのアクセス可能な温度で安定した結晶構造のための新しい経路を提供します.
科学分野:
- マテリアルサイエンス 材料科学
- 超分子化学 超分子化学
- オーガニック・エレクトロニクス
背景:
- ペリレンビシミド (PBIs) は,オーダーされた超分子構造を形成することが知られている.
- 平面型PBIsに関する以前の研究では,2Dおよび3D配列の温度に依存した形成が示されました.
- PBIsの機能化は,その自己組み立て動作に大きく影響を与える可能性があります.
研究 の 目的:
- 非平面的,柔軟な四塩化PBI (Cl4PBI) デリバティブの超分子組成を調査する.
- Cl4PBIの自己組織を水素化および半フッ素化デンドロンと非塩素化PBIsと比較する.
- アクセシブルな温度で安定した結晶アセンブリを達成するための新しい経路を探求する.
主な方法:
- 異なるリンク長 (m = 0,1,2,3) と二酸化エチレン) リンク器 (m = 2EO) を介してAB3ミニデンドロンで機能化されたCl4PBIの合成.
- 微分スキャニング熱計 (DSC),X線 difraktion (XRD),および固体核磁共振 (NMR) を用いた超分子構造の特徴化.
- 熱力学および運動制御下での自己組み立ての分析.
主要な成果:
- Cl4PBIは,水素化されたデンドロンが,熱力学的な制御 (m=0,2) の下で,独占的に3Dの結晶配列に自己組織化しており,これは,より秩序が低い分子構成要素にとって予期せぬ結果である.
- 半化デンドロン化Cl4PBIは,2Dの柱状六角形配列 (m=3,運動制御) と珍しい2Dの蜂巣状六角形相 (m=2EO,熱力学制御) を形成した.
- これらのCl4PBI化合物は,平面型PBIsで以前に達成されたよりも低い温度で熱力学的な制御によって安定した結晶組成を可能にします.
結論:
- Cl4PBIの非平面的および柔軟な性質は,特定のデンドロン機能化と組み合わせて,超分子組成においてより高い3D秩序を促進します.
- 熱力学的制御は,より秩序が低い分子成分から安定した,秩序のある3D結晶構造を作成するための実行可能な戦略を提供します.
- これらの発見は,構造分析と技術的な応用のために,調節可能な自己組み立てを備えた材料を設計するための新しい道を示しています.
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