双核复合体的非辐射衰变机制:密度函数理论研究研究
Guo-Jun Kang1, Yong-Fei Wu1, Xue-Feng Ren1
1Carbon Neutrality Institute and School of Chemical Engineering & Technology, China University of Mining and Technology, Xuzhou 221008, China. renxf@cumt.edu.cn.
Physical chemistry chemical physics : PCCP
|September 5, 2024
概括
双核 (III) 复合体对其非辐射衰变的理解有限. 本研究阐明了该机制,确定了弱的Ir-N键和特定的失活路径,这些路径对于开发高效的红色发射材料至关重要.
科学领域:
- 无机化学 无机化学 有机化学
- 材料科学 材料科学 材料科学
- 计算化学计算化学
背景情况:
- 双核金属复合物,特别是 (III) 复合物,在光发光和催化方面表现出潜力.
- 这些复合物的非辐射衰变机制尚不清楚,这限制了它们的应用.
- 了解衰变路径对于设计高效的发光材料至关重要.
研究的目的:
- 阐明二核 (D1和D2) 复合体和单核 (M1) 的非辐射衰变机制.
- 确定控制衰变过程的关键步骤和能量障碍.
- 为开发高效发射红色的双核 (III) 材料提供见解.
主要方法:
- 使用密度函数理论 (DFT) 的计算.
- 对非辐射衰变路径的分析,包括弗兰克 - 康登地区和交叉的最小能量层 (MESX).
- 研究电子吸收组对能量屏障的影响.
主要成果:
- 非辐射衰变通过弱的Ir-N键发生,导致三重金属中心 (MC) 状态.
- 禁用途径3MLCT → TS → 3MC→ MESX是决定性的步骤.
- 与M1相比,双核复合体D1和D2对MESX的能量障碍较低,这解释了它们较弱的红色辐射.
结论:
- 这项研究阐明了双核 (III) 复合物的非辐射衰变机制.
- 穿越最低能量层 (MESX) 的较低能量的障碍物对双核综合体的减排负责.
- 引入电子吸收组可以增加能量障碍,提供增强发光和开发高效发射红色的双核材料的策略.
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