使用介质效应来调整双金属和小金属化合物的Delta E(1/2) 值
Frédéric Barrière1, Nicole Camire, William E Geiger
1Department of Chemistry, University of Vermont, Burlington, Vermont 05405, USA.
Journal of the American Chemical Society
|June 20, 2002
概括
该研究测量了各种电解质中的复合物的氧化还原潜力. 溶剂和盐的选择显著影响电子转移,影响多氧化系统中的电子相互作用.
科学领域:
- 电化学 电化学 电化学
- 有机金属化学 有机金属化学
- 材料科学 材料科学 材料科学
背景情况:
- 双 () 丁基 (1) 和四 (铁) 丁基 (2) 是具有多个氧化还原中心的关键有机金属化合物.
- 了解氧化还原潜力的行为对于设计先进的电子材料至关重要.
- 对于复杂的系统,对电子转移过程的中等效应尚未完全阐明.
研究的目的:
- 研究非水性电解质对复合物1和2的氧化还原潜力的影响.
- 量化溶剂极性,供体强度和电解质组成对电子转移的影响.
- 探索多氧化化合物中介质效应和电子相互作用之间的关系.
主要方法:
- 对复合体1和2进行了电化学测量 (循环电压测量).
- 使用了各种非水性溶剂,包括和二甲.
- 使用了不同的电解盐,具有不同的阴离子和离子大小,例如[NBu4]Cl和Na[B(C6H3(CF3)2) 4].
- 进行了半波电位差异 (ΔE1/2) 和比值常数 (Kcomp) 的分析.
主要成果:
- 综合体1的ΔE1/2值从212mV到850mV有显著的变化,这表明压缩常数发生了很大的变化.
- 综合体2展示了六个可逆的氧化还原过程,氧化和还原波扩散对电解质介质敏感.
- 对于阴离子产品,最大 ΔE1/2 发生在具有特定盐组合 (大离子,小阴离子) 的低极性溶剂中.
- 在类似的条件下,观察到离子产品的最小 ΔE1/2,包括2/22−的两电子波.
- 溶解和离子配对效应被确定为影响氧化还原行为的关键因素.
结论:
- 介质效应,包括溶解和离子配对,在调节有机金属复合物的氧化还原潜力方面发挥着重要作用.
- 选择非水性电解质可以在战略上用于控制和调整电子转移过程.
- ΔE1/2 值是评估氧化还原中心之间的电子通信的有价值指标,但需要仔细考虑介质效应.
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