Experimental and quantum chemical characterization of the water oxidation cycle catalysed by [RuII(damp)(bpy)(H2O)]2+
Experimental and quantum chemical characterization of the water oxidation cycle catalysed by [RuII(damp)(bpy)(H2O)]2+
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DOI：
10.1039/c2sc20399e
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发表时间：
2012-07
期刊：
影响因子：
8.4
通讯作者：
Laura Vigara;M. Z. Ertem;Nora Planas;Fernando Bozoglián;Nils Leidel;H. Dau;M. Haumann;L. Gagliardi;C. Cramer;A. Llobet
中科院分区：
文献类型：
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作者：
Laura Vigara;M. Z. Ertem;Nora Planas;Fernando Bozoglián;Nils Leidel;H. Dau;M. Haumann;L. Gagliardi;C. Cramer;A. Llobet
用质谱和测压法测定了[RuII（damp）（bpy）（H_2O）]~（2+）的水氧化催化活性。催化循环的机制的细节进行了研究，实验和使用DFT和CASSCF/CASPT 2计算。这种钌（II）络合物和更高度氧化的催化中间体的表征已通过紫外可见光谱和XAS光谱，以及通过电化学技术完成。XAS光谱与CASSCF/CASPT 2计算的比较提供了深入了解更高度氧化的物种的电子结构，特别是氧化发生在Ru-O片段的两个原子的程度。18 O-标记实验表明，O-O键的形成步骤通过水亲核攻击机制进行，和详细的DFT分析的催化循环预测，该步骤是速率决定和发生的正式Ru（V）O物种。一些替代的更高能量的途径也被表征，以提供整个系统的更完整的视野。
The water-oxidation catalytic activity of [RuII(damp)(bpy)(H2O)]2+ has been determined from manometric and mass spectroscopy studies. Mechanistic details of the catalytic cycle have been studied both experimentally and using DFT and CASSCF/CASPT2 calculations. Characterisation of this Ru(II) complex and more highly oxidized catalytic intermediates has been accomplished through UV-vis and XAS spectroscopy, as well as through electrochemical techniques. Comparison of XAS spectra with CASSCF/CASPT2 calculations provides insight into the electronic structures of the more highly oxidized species, especially the degree to which oxidation occurs over both atoms of the Ru–O fragment. 18O-labelling experiments indicate that the O–O bond formation step proceeds via a water nucleophilic attack mechanism, and a detailed DFT analysis of the catalytic cycle predicts that step to be rate-determining and to take place for a formal Ru(V)O species. A number of alternative higher energy pathways have also been characterised in order to provide a more complete vision of the whole system.