在Carbene Zinc中的高效热激活延迟光的结构控制(II) 二氧化酸盐
Mousree Mitra1, Ondřej Mrózek1, Markus Putscher2
1Faculty of Chemistry and Chemical Biology, TU Dortmund University, Otto-Hahn-Str. 6, 44227, Dortmund, Germany.
Angewandte Chemie (International ed. in English)
|December 8, 2023
概括
新的 (II) 复合物表现出高效的热激活延迟光 (TADF),在光子应用中为重金属发射器提供了一个有希望的替代方案. 它们的设计建立了关键的结构-属性关系,用于涉及三重激发状态的发光.
科学领域:
- 材料科学 材料科学 材料科学
- 摄影应用 摄影应用
- 协调化学 协调化学
背景情况:
- 地球上丰富的发光金属复合物被寻求作为三重发射器的4d/5d过渡金属的替代品.
- 铜 (I) 复合物已被广泛研究,但 (II) 光发的结构-性质关系缺乏.
研究的目的:
- 在 (II) 复合体中建立有效发光的结构-属性关系.
- 为先进的光子应用设计新的 (II) 复合物.
主要方法:
- 合成具有捐赠体-接受体图案的单体碳酸二甲酸 (CZT).
- 高级的DFT/MRCI计算,以调查电子结构和兴奋状态.
- 对辐射速率常数和反向系统间交叉效率的分析.
主要成果:
- 实现了ZnII化合物的前所未有的辐射速率常数 (kTADF = 1.2×106 s-1)
- 已经证明了高效的热激活延迟光 (TADF).
- 确定了连接体方向 (36-40°二面角) 作为有效反向系统间交叉 (rISC) (109 s-1) 的关键.
结论:
- 供体-受体基因中的联体导向是控制ZnII复合体中的TADF的关键.
- 小的能量差距 (ΔES1-T1 ≈ 56 meV) 和硫介导的旋转轨道合 (SOC) 提高了TADF的效率.
- 这些发现为开发高效的地球丰富的三重排放器铺平了道路.
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