デンドリメリック分子ローターのコア,枝,および周辺の芳香グループでの急速な回転運動によって反映された結晶流動性
Xing Jiang1, Zachary J O'Brien1, Song Yang1
1Department of Chemistry and Biochemistry, University of California , Los Angeles, California 90095-1569, United States.
Journal of the American Chemical Society
|March 15, 2016
まとめ
この研究は,デンドリメリック・ローター分子が,急速に回転する芳香質のグループで緩やかに詰まった結晶を形成することを明らかにしています. 超分岐構造により 静的電位ではなく 結晶の流動性によって 急速な分子動力学が可能になります
科学分野:
- 固体化学
- 超分子化学
- 材料科学
背景:
- アンフィダイナミック結晶は,パッキング密度が低い静的および移動的成分を特徴としています.
- ダイナミックな材料を設計するためのユニークなハイパーブランチ構造をデンドリメリック分子は提供します.
研究 の 目的:
- デンドリメリック・ローター分子 (化合物2) を合成し,特徴づけること.
- コンパウンド2の固体ダイナミクスとその構造的影響を調査する.
- 分子運動を制御する要素を理解するために
主な方法:
- 化合物2の収束合成戦略
- 構造分析のための単一結晶X線 difraktion.
- 分子運動を研究するために,同位体で変数温度2H NMRスペクトロシー.
主要な成果:
- 化合物2は,有意な溶媒を含有した低密度の結晶を形成する.
- すべてのアロマティックグループ (中央,分岐,および周辺フェニル) は,周りの温度でメガヘルツの回転ダイナミクスを示します.
- アレニウスの分析は,ダイナミクスは,静的なポテンシャルではなく,温度に依存する構造的変動と結晶流動性によって支配されていることを示しています.
結論:
- デンドリメリック・ロータ2の超分岐構造は,低密度パッキングと固体状態での急速な分子ダイナミクスを促進する.
- これらの結晶の分子運動は静的なエネルギー障壁ではなく,結晶の流動性のようなダイナミックなプロセスによって影響されます.
- この研究は,制御された分子運動を持つアンフィダイナミック結晶の設計に関する洞察を提供します.
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