增强的系统间交叉,但在介绍中介电荷转移状态后仍有光在半导体中[Zn(bpy)
Julia Kuhnt1, Mousree Mitra1, Sabyasachi Maity1
1Faculty of Chemistry and Chemical Biology, TU Dortmund University, Otto-Hahn-Str. 6, D-44227 Dortmund, Germany.
The journal of physical chemistry letters
|June 12, 2024
概括
(II) 复合物通常是光的. 然而, (II) 复合体中的一个半联体结构意外地改变了其光物理特性,有利于系统间交叉而不是光.
科学领域:
- 摄影化学的使用.
- 协调化学 协调化学
- 量子化学 是一个量子化学.
背景情况:
- 光活性 (II) 复合体通常会从单点激发状态表现出光,这是由于旋转轨道合较弱造成的.
- 在这样的系统中,三重状态的光通常是禁止的.
- 据称,之前报告的一种 (II) 三 (二) (二) 的半结衍生物 ([Zn (bpy) 3 2+)) 经历了高效的系统间交叉 (ISC) 到三重体状态.
研究的目的:
- 解决[Zn(bpy) 3 2+及其半导体的兴奋状态行为.
- 为了调查预期和报告的光物理性质之间的差异,hemicage复合体.
- 阐明连接体结构在控制辐射和非辐射衰变途径中的作用.
主要方法:
- 可变温度光物理测量在溶液和固态.
- 时间分辨率光谱学.
- 高层次的理论计算.
主要成果:
- 无论是[Zn(bpy) 3 2+还是其半衍生物在室温下都表现出光.
- 与母体复合体 (2 × 10^8 s^-1) 相比,hemicage复合体显示出显著减少的光速常数 (1.2 × 10^6 s^-1).
- 半导体结构引入了电荷转移状态,使ISC加速到3LC(bpy) 状态 (从350秒到82秒).
- 对于这两种化合物来说,在低温下仅在毫秒时间尺度上观察到弱光.
结论:
- 电荷转移状态在半导体连接体支架中的存在是导致光物理行为的改变的原因.
- 半膜结构促进ISC,但光在室温下仍然是占主导地位的途径.
- 初步报告的定量ISC和快速光在hemicage复合体可能是不准确的.
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