结构控制 1A2u-3A2u 跨系统交叉在二 ((II,II) 复合体中的结构控制
Alec C Durrell1, Gretchen E Keller, Yan-Choi Lam
1Beckman Institute, California Institute of Technology, Pasadena, California 91125, USA.
Journal of the American Chemical Society
|August 8, 2012
概括
与其母体Ptpop复合物相比,新型的化化复合物Ptpop-BF2) 的辐射衰变速度明显更快,系统间交叉 (ISC) 速度更慢. 这种增强是由于减少了旋转轨道合和有限的溶剂访问.
科学领域:
- 摄影化学的使用.
- 无机化学 无机化学 有机化学
- 材料科学 材料科学 材料科学
背景情况:
- 双酸盐 (II) 复合物以其独特的光物理性质而闻名.
- 修改连接体环境可以为特定应用调整这些特性.
- 了解衰变途径对于开发高效光材料至关重要.
研究的目的:
- 为了研究per (difluoroboro) tetrakis (pyrophosphito) diplatinate (II) (Pt (pop-BF (2))) 的光物理特性.
- 为了比较其辐射和非辐射衰变速率与父复合体,Pt(pop).
- 阐明影响系统间交叉 (ISC) 路径的因素.
主要方法:
- 可变温度光量子产量和寿命测量.
- 对辐射衰变速率 (k (r)) 的分析.
- 确定系统间交叉 (ISC) 激活能量 (E(a)).
主要成果:
- Pt(pop-BF(2)) 表示辐射衰变速率大小的数量级大于Pt(pop).
- 在Pt(pop-BF(2)) 中的ISC通路显著较慢 (18x和142x) 比在Pt(pop).
- ISC减速的原因是旋转轨道合的减少和溶剂获取的减少.
结论:
- 由于更快的辐射衰变,Pt(pop-BF(2)) 复合体显示了增强的光发光效率.
- 在Pt中P-O-P框架的刚性增加 (pop-BF) 阻碍了对称性降低的扭曲,影响ISC.
- 这些发现为设计先进的基光材料提供了洞察力.
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