光を機械的な作業に変換するダイアリレチンのコクリスタルです
Masakazu Morimoto1, Masahiro Irie
1Department of Chemistry and Research Center for Smart Molecules, Rikkyo University, Nishi-Ikebukuro 3-34-1, Toshima-ku, Tokyo 171-8501, Japan.
Journal of the American Chemical Society
|September 23, 2010
まとめ
この研究では,紫外線と可視光で逆転的に曲げる光色共結晶が示されています. これらの分子結晶は重い物体を持ち上げることができ,重要な機械的ストレスを生成します.
科学分野:
- マテリアルサイエンス 材料科学
- クリスタログラフィーです.
- フォトケミストリー フォトケミストリー
背景:
- フォトクロミック素材は,光にさらされると色が変わります.
- 分子結晶は,ユニークな機械的性質を備えています.
- ダイアリエーテンの誘導体は,その光色特性で知られています.
研究 の 目的:
- 新しいダイアリレチン-ペルフローロナフタレンコクリスタルの光学効果を調査する.
- リバーシブルな曲げ運動とその背後にあるメカニズムを特徴付けるために.
- 分子アクチュエータにおけるこの材料の潜在的な応用を探求する.
主な方法:
- 1,2-bis(2-メチル-5-(1-ナフチル) -3-チエニル) ペルフローロcyclopentene (1o) と perfluoronaphthalene (FN) の共結晶の合成と特徴付け.
- 水晶の変形を研究するために,X線でインシット結晶分析を行う.
- 分子結晶のキャンティレバーの機械試験.
- 曲げ運動の低温動的測定. 曲げ運動の低温動的測定.
主要な成果:
- 1o·FN共結晶は,交互のUVと可視光照射で可逆的な屈曲を示し,250サイクル以上繰り返すことができます.
- 結晶の変形は,ダイアリレチンの光回転によって引き起こされるb軸の延長に起因する.
- 曲げ運動は,マイクロ秒の時間スケールでアニソトロプ的膨張で,4.7Kでも発生します.
- 分子結晶のキャンティレバーは,重量の200~600倍もの物体を持ち上げることができます.
- 生成されるストレスは44MPaに達し,ピエゾ電気材料と比較できます.
結論:
- ダイアリレチン-パーフローロナフタレンコクリスタルは,重要な光力学的性質を示しています.
- この素材は,効率的で繰り返される光誘発曲折と機械的な作業を備えています.
- この研究は,高度な分子機械とアクチュエータの開発への道を開く.
関連する概念動画
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