在共价连接的同面基四二元体中单片裂变
Nadezhda V Korovina1, Saptaparna Das1, Zachary Nett1
1Department of Chemistry, University of Southern California , Los Angeles, California 90089, United States.
Journal of the American Chemical Society
|December 24, 2015
概括
在新型四二元中,单片裂变有效地从一个单片激子产生两个三重激子. 这一过程对于有效的三重生成至关重要,特别是当三重能量转移到附近的分子时.
科学领域:
- 摄影化学
- 有机电子
- 材料科学
背景情况:
- 单子裂变是从单个光子产生多个激子的关键过程.
- 了解有机分子中的单片裂变对于光伏和光电子技术的发展至关重要.
研究的目的:
- 为了研究互烯重叠对共价连接的5-乙-四二聚体的单片裂变效率的影响.
- 在BET-X和BET-B化合物中阐明单片裂变和随后三片裂变的机制和动力学.
主要方法:
- 两种ET二元体 (BET-X和BET-B) 的合成和结晶学表征, π轨道重叠变化.
- 在溶液,PMMA和薄膜中进行吸收和发射光谱研究.
- 超快速光谱和第一原理计算以确定反应动态和能量.
主要成果:
- 在无形薄膜中,BET-B表现出高效的单片裂变 (154%的三片裂变率).
- 在溶液和PMMA中,BET-B在2ps内形成相关的三对 (1) ((T1T1),需要能量转移以产生自由三.
- 与BET-B相比,BET-X显示了更快的中间形成 (<180 fs) 和衰变.
- 基于第一原理的计算显示,BET-B的单片裂变速度比晶体四更快100倍,这是由于增强的合和有利的能量.
结论:
- 分子排列和π轨道重叠显著影响单片裂变效率和动力学.
- 相关的三胞胎对状态是关键的中间体,随后的能量转移对于生成自由三胞胎至关重要.
- 对于需要通过单片裂变高效的三重生成的应用,BET-B显示出有前途的潜力.
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