在刚性聚合物薄膜中激发状态间隔传递
Cavan N Fleming1, Dana M Dattelbaum, David W Thompson
1Department of Chemistry, University of North Carolina, Chapel Hill, North Carolina 27599, USA.
Journal of the American Chemical Society
|July 17, 2007
概括
在PMMA中稳定复合物使得详细的光物理研究成为可能,揭示了对刚性介质中电子转移机制的见解. 这项工作增强了对金属对联体电荷转移特性的理解.
科学领域:
- 无机化学 无机化学 有机化学
- 摄影化学的使用.
- 材料科学 材料科学 材料科学
背景情况:
- 在光化学和电子转移研究中,聚烯基复合物至关重要.
- 光化学连接体损失可能会阻碍这些复合物的详细光物理特征.
- 聚甲基酸 (PMMA) 为稳定反应性中间体提供了一个潜在的介质.
研究的目的:
- 在PMMA矩阵中稳定一个特定的联结桥接复合体,cis,cis-[(bpy) 2ClRu(pz) RuCl(bpy) 2+ .
- 为了研究稳定复合物的金属到质电荷转移 (MLCT) 光物理性质.
- 分析光化学生成混合价值物种的间隔传递 (IT) 波段特征.
主要方法:
- 在PMMA中光化学制备和稳定复合物.
- 测量排放和短暂吸收光谱的测量.
- 对近红外区域间隔传输带的光谱分析.
- 在刚性 (PMMA) 和流体 (CD3CN) 介质中的光谱数据的比较.
主要成果:
- 复合物 (1) (((PF6) 2在PMMA中成功稳定,防止光化学带损失.
- 测量了发射和短暂吸收光谱,以特征MLCT属性.
- 在PMMA中观察到混合价值形式 (1*(PF6) 2) 的间隔转移吸收带.
- 与CD3CN相比,在PMMA中观察到IT频段能量和宽度的减少,这归因于刚性介质.
结论:
- PMMA为联结桥路的复合物提供了有效的稳定性,促进了光物理测量.
- 该研究详细比较了不同介质中的桥接联体特性 (pz vs. pz(-*)).
- 一个解释刚性与流体介质对IT频段特征的影响的模型提供了对电子传输过程的洞察.
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