水 (在水中) 作为协同的质子电子转移中的内在有效的质子受体
Julien Bonin1, Cyrille Costentin, Cyril Louault
1Laboratoire d'Electrochimie Moléculaire, Unité Mixte de Recherche Université - CNRS No 7591, Université Paris Diderot, Bâtiment Lavoisier, 15 rue Jean de Baïf, 75205 Paris Cedex 13, France.
Journal of the American Chemical Society
|April 12, 2011
概括
水在电子转移反应中充当质子受体. 这项研究揭示了一种涉及水群沿着质子转移的机制,这对于生物质子运输至关重要.
科学领域:
- 摄影化学的使用.
- 物理化学 物理化学
- 生物物理化学 生物物理化学
背景情况:
- 质子和电子的转移是化学和生物过程的基础.
- 了解水作为质子受体的作用是阐明反应机制的关键.
研究的目的:
- 调查由光化学生成的 (III) 三 (二) (Ru (III) (bpy)) [3]介导的 (PhOH) 在水中的氧化机制.
- 描述水在协同的质子-电子转移反应中作为质子受体的作用.
主要方法:
- 动力学研究涉及速度常数随温度和驱动力的变化.
- 在不同温度下分析H/D动态同位素效应.
- 与标准基,酸反应特征的比较.
主要成果:
- 反应机制是由三个内在参数决定的:重组能量,预指数因子 (振动合) 和距离灵敏度参数.
- 电子转移与Grotthus类型的质子转移相协调.
- 电荷转移发生在水集群上,表明水的独特作用.
结论:
- 发现了一种沿着水链运输质子的新机制,加上电子转移.
- 这种机制为生物系统中的质子转位提供了洞察力.
- 强调了水作为协同的质子-电子转移反应中的质子受体的特殊特征.
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