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在连续离子对中对可见光敏感的氧化
Guocan Li1, Wesley B Swords1, Gerald J Meyer1
1Department of Chemistry, University of North Carolina at Chapel Hill , Chapel Hill, North Carolina 27599, United States.
Journal of the American Chemical Society
|September 22, 2017
概括
胺添加到一个复合体 ([Ru(deeb) ((bpz) 2+) 形成具有不同的光物理性质的离子对. 第二个离子对 ([Ru2+, 2Br−]*) 由于电子转移速度较慢,显示了增强的发光.
科学领域:
- 协调化学
- 光物理学
- 电子转移
背景情况:
- (II) 聚基复合物因其光物理和电子转移特性而被广泛研究.
- 离子配对可以显著影响充电金属复合物的兴奋状态行为.
- 了解离子对形成及其对电子转移的影响对于设计功能性材料至关重要.
研究的目的:
- 为了研究二甲中[Ru ((deeb)) ((bpz)) 2+和离子之间的离子对的形成.
- 描述这些离子配对物种的光物理和电子转移特性.
- 阐明结构和电子因素控制观察到的发光和电子转移变化.
主要方法:
- 将化物定位为二甲溶液的[ru{deeb}{bpz}2]2+.
- 包括1H NMR和光发光 (PL) 测量的光谱分析.
- 密度函数理论 (DFT) 计算以补充实验结构数据.
- 动力学研究以确定电子转移速率常数.
主要成果:
- 两个连续的离子配对物种[Ru2+,Br−]+和[Ru2+,2Br−]*,形成了不同的平衡常数.
- 第一个离子对 ([Ru2+, Br−]+*) 是非发光的,而第二个 ([Ru2+, 2Br−]*) 则表现出部分发光回收 (τ = 65 ± 5 ns).
- 原子 (Br•) 被确定为主要的电子转移产物,形成 Br2•−.
- 电子传递速率常数 (ket) 被确定并与DFT计算中的库伦比工作量 (ΔGw) 相对应.
结论:
- 化物与[Ru(deeb) ((bpz) 2+的离子配对显著改变了其光物理和电子转移特性.
- 第二个离子对的增强发光归因于电子转移的不太有利的吉布斯自由能量变化.
- DFT计算为离子配对和电子转移过程的结构和能量方面提供了宝贵的见解.
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