一个[Co(III) 3Co(IV) O4]集群的电子结构描述:在催化水氧化过程中,一种对磁性中间体的模型
J Gregory McAlpin1, Troy A Stich, C André Ohlin
1Department of Chemistry, University of California, One Shields Avenue, Davis, California 95616, United States.
Journal of the American Chemical Society
|September 15, 2011
概括
这项研究使用电子偏磁共振 (EPR) 光谱和电子结构计算来分析四聚合物. 结果揭示了无对电子旋转在核心原子中的脱局,有助于理解氧化水催化剂.
科学领域:
- 无机化学 无机化学 有机化学
- 频谱学是一种光谱学方法.
- 计算化学计算化学
背景情况:
- 酸 (Co-Pi) 催化剂对于水的氧化至关重要.
- 了解集群的电子结构是催化剂效率的关键.
- 具有立方体结构的四合体提供了对催化机制的洞察力.
研究的目的:
- 为了研究一个特定的四聚合物的电子结构, [Co(4) O(4) ((C(5) H(5) N) ((4) ((CH(3) CO(2)) ((4))) ((+) (1(+)).
- 为了将1(+) 的光谱特性与酸氧化水催化剂进行比较.
- 为了阐明四重体内未配对电子旋转的脱局.
主要方法:
- 多频电子偏磁共振 (EPR) 光谱. 多频电子偏磁共振 (EPR) 光谱.
- 戴维斯电子核双共振 (ENDOR) 和米姆斯 (1) H ENDOR.
- 多频 (14) N 电子自旋回声外调制 (ESEEM) 光谱.
- 密度函数理论 (DFT) 的计算.
主要成果:
- 1(+) 的 EPR 频谱表明八个核心原子的不配对的自转转移.
- ENDOR和ESEEM的数据显示了与核和原子的超细合.
- DFT计算证实了未配对电子的脱位.
- 离子处于低自旋配置,具有小数电子孔.
结论:
- 在 1 ((+) 中的无对电子旋转被移到和氧核上.
- 1(+) 的电子结构为理解酸水氧化催化剂提供了一个模型.
- 光谱和计算方法一起阐明了团中的自旋分布.
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