アゾベンゼン光異性化のグローバル反応座標を機械で探す
Pedram Tavadze1, Guillermo Avendaño Franco1, Pengju Ren2,3
1Department of Physics and Astronomy, West Virginia University , Morgantown, West Virginia 26506-6315, United States.
Journal of the American Chemical Society
|December 14, 2017
まとめ
アゾベンゼンの光同位化は中央のC-NN-C二面角によって引き起こされる. グローバル反応座標は,逆転補助回転が,この光活性化機械的変換に大きく寄与することを明らかにします.
科学分野:
- 写真化学
- 分子力学
- 有機化学
背景:
- アゾベンゼンは,光異性化による機械的変化を研究するための重要な染色体である.
- C-NN-C二面角は,伝統的にアゾベンゼンシストランス異体化の主な反応座標と考えられている.
研究 の 目的:
- アゾベンゼン光異性化のためのすべての内部座標を含むグローバル反応座標を開発し分析する.
- 各内部座標が全体的な光異性化メカニズムに与える貢献度を定量化する.
- トランス・トゥ・シスエネルギープロフィールにおける主要な内部座標の変化をマッピングする.
主な方法:
- グローバル反応座標を定義する計算分析.
- 個々の内部コーディネート貢献の定量化
- 内部座標ダイナミクスのエネルギープロファイルマッピング
主要な成果:
- 中央のC-NN-C二面角は,アゾベンゼン光異性化反応座標における支配的要素である.
- 4つの隣接する二面角 (C-C-NN) によって誘導される反転補助回転は,全体的なメカニズムに大きく (約50%) 貢献する.
- 逆転補助の回転過程で隣接するC-C-Nの角度での変化は最小でした.
結論:
- アゾベンゼン光異性化には,中央二面角を超えた内部座標の複雑な相互作用が含まれる.
- 逆転による回転は,以前は過小評価されていたが,アゾベンゼン光異性化機構の重要な構成要素である.
- この詳細な座標ダイナミクスを理解することで 光で活性化された分子変換の 詳細な洞察が得られます
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