通过控制刺激性合来最大限度地减少分子聚合物的非辐射衰变
Yuanheng Wang1, Jiajun Ren2, Zhigang Shuai3,4
1MOE Key Laboratory of Organic OptoElectronics and Molecular Engineering, Department of Chemistry, Tsinghua University, 100084, Beijing, People's Republic of China.
Nature communications
|August 19, 2023
概括
分子聚合物可以通过抵消能量差距法 (EGL) 来实现近红外 (NIR) 辐射. 在这些材料中,激子脱局的增加导致非单调的减少,然后增加非辐射衰变速率.
科学领域:
- 量子化学 是一个量子化学.
- 材料科学 材料科学 材料科学
- 频谱学是一种光谱学.
背景情况:
- 能源差距法 (EGL) 预测非辐射衰变率 (knr) 增加,能量差距更小,限制近红外 (NIR) 辐射.
- 假设在分子聚合物中的激发离位化能够克服EGL,从而使NIR发射成为可能.
研究的目的:
- 开发和应用一种高精度的计算方法,用于评估分子聚合物的非辐射衰变速率.
- 调查激子脱局对非辐射衰变速率和NIR发射特性的影响.
主要方法:
- 开发近乎精确的时间依赖密度矩阵重规范化组 (TD-DMRG) 方法.
- 激子 - 声子合分子聚合物的系统数值模拟 (二极体,1D链,2D网格).
主要成果:
- 非辐射衰变速率 (knr) 呈现出异常的非单调行为与增加的激发性合:它减少,达到最低,然后增加.
- 这种行为源于降低能量差距和降低有效的电子-声波合之间的相互作用.
- 最低knr的最佳激发性合大约是单体重组能量的一半,受系统大小,维度和温度的影响.
结论:
- 刺激子移位可以有效调整分子聚合物的非辐射衰变速率,为高效的NIR发射器提供途径.
- TD-DMRG方法为理解复杂分子系统中的光物理过程提供了一个强大的工具.
- 这些发现为通过控制激发性合来设计新型NIR发射材料提供了关键的见解.
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