アクティベーションレス多部位協調型陽子電子トンネリング

Miriam A Bowring^1,2,3, Liam R Bradshaw², Giovanny A Parada¹

¹Department of Chemistry , Yale University , New Haven , Connecticut 06520 , United States.

Journal of the American Chemical Society

|May 31, 2018

まとめ

研究者達は素早く陽子と電子を交換する分子のトライアードを設計しエネルギー利用に不可欠ですこのプロセスは温度に関係なく量子トンネリングによって起こり効率的なエネルギー変換の洞察力を提供します

科学分野:

写真化学
分子生物物理学
量子化学について

背景:

陽子と電子の移動はエネルギー変換と貯蔵のプロセスに不可欠です
人工光合成や燃料電池などの技術の進歩にはこれらの電荷伝送メカニズムを理解し制御することが極めて重要です

研究の目的:

素早く光誘導された多部位協調型陽子電子移転 (MS-CPET) を可能にする新しい分子システムを設計し,研究する.
このMS-CPETプロセスのメカニズムと温度依存性を解明し,陽子と電子のトンネリングの役割に焦点を当てます.

主な方法:

アントラセン-フェノル-ピリジン分子トライアードの設計
光 quenchingと一時的な吸収スペクトロスコーピーを利用します.
溶液とグラスで幅広い温度 (5.5Kから350K) で実験を行う.

主要な成果:

設計された分子トライアードは,速度定数 3.2 × 10^10 s^-1 の 298 K で急速な MS-CPET を示す.
反応速度と運動同位体効果 (KIE) は,温度から5.5Kから90Kまで独立しており,アルヘニウス活性化エネルギーはゼロである.
145Kから350Kまで観測された最小の温度依存は,支配的なトンネリングメカニズムを示唆しています.

結論:

観測されたMS-CPET反応は,主に陽子と電子の両方の量子トンネル化によって異なる方向に進みます.
速度の定数は陽子と電子の同時ダブルトンネリングの確率を直接反映します
この研究は,エネルギー変換と貯蔵に関連する効率的で熱的に独立した電荷伝送を調査するための分子プラットフォームを提供します.

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