トリアリルトリアジンのステリック・リプルション・ドリブン・クラッチ・スタック:相関する分子回転と結晶固体の熱反応ギアシフト
Mingoo Jin1, Ryunosuke Kitsu2, Natsumi Hammyo2
1Institute for Chemical Reaction Design and Discovery (WPI-ICReDD), Hokkaido University, Sapporo, Hokkaido 060-8628, Japan.
Journal of the American Chemical Society
|December 7, 2023
まとめ
新しく開発されたトリアリトリアジンロータは,独特の相関分子運動を持つ柱状構造を形成します. これらの動きは,温度誘発の相変化によって切り替えられ,分子レベルのギアシフト制御を提供します.
科学分野:
- 超分子化学
- 材料科学
- 固体化学
背景:
- トリアリトリアジン系は,分子機械におけるその可能性で知られている.
- 固体状態での分子運動の制御は 重要な課題です
- 先進的なアプリケーションでは,予測可能で切り替え可能なダイナミック特性を備えた材料を設計することが重要です.
研究 の 目的:
- トリアリトリアジンの新型ローターを 開発する
- これらのローターの結晶構造と分子動態を調査する.
- 熱的に誘導された相変遷を介して分子運動を制御する可能性を探求する.
主な方法:
- 新型トリアリトリアジン・ローターの合成
- 変数温度固体2H NMRスペクトル
- 結晶構造と相変化を分析するためのX線 difraktion研究.
主要な成果:
- 結晶段階の柱状の積み重なったクラッチ構造の形成.
- 2つの異なる相互変換可能な相関分子運動 (フラッピングと180°回転) の観察.
- 熱的に誘導された結晶から結晶の相移行によって達成された運動の間の切り替え.
- 両方の回転運動に関連した負のエントロピー変化.
結論:
- 巨大なステータルからの ステリック反発は 分子間堆積と相関運動を 誘導します
- 熱的に誘発された相変換は分子回転に対する可逆的な制御を提供します.
- この戦略は,調節可能な分子ダイナミクスとギアシフト機能を持つ材料を設計するための有望な経路を提供します.
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