对2和2,7功能化烯衍生物的光物理性质的实验和理论研究
Andrew G Crawford1, Austin D Dwyer, Zhiqiang Liu
1Department of Chemistry, Durham University, South Road, Durham DH1 3LE, United Kingdom.
Journal of the American Chemical Society
|July 15, 2011
概括
烯衍生物上的替代物位置显著改变光物理性质. 在2位和2,7位的衍生品表现出独特的"像pyrene"和"受替代品影响"的激发,与1位替代品不同.
科学领域:
- 光化学和光物理学
- 有机化学 有机化学
- 材料科学 材料科学 材料科学
背景情况:
- 皮雷尼衍生物因其独特的光物理性质而受到广泛研究.
- 替代物在烯核上的位置影响电子过渡和兴奋状态行为.
- 了解这些结构-属性关系对于设计新型功能材料至关重要.
研究的目的:
- 为了研究和比较二,二,三,七和一位置换的烯衍生物的光物理性质.
- 根据分子轨道理论和替代物效应,合理化观察到的电子激发差异.
- 合成和描述一系列新的2R-pyrene和2,7-R2-pyrene.
主要方法:
- 各种2-R-pyrene和2,7-R2-pyrene的合成,与1-R-pyrene类似物相比具有特性.
- 实验测量包括吸收和发射光谱,光量子产量和光寿命.
- 使用B3LYP和CAM-B3LYP函数的时间依赖密度函数理论 (TD-DFT) 计算.
主要成果:
- 与1替代衍生物相比,2和2,7替代的烯表现出不同的光物理行为,对S(1) 和S(2) 激发有特定的影响.
- 观察到高光量子产量 (0.190.93) 和长光寿命 (通常为5080 ns,一个衍生品高达622 ns).
- TD-DFT计算成功地重现了激发波长的实验趋势,验证了理论方法.
结论:
- 烯的HOMO和LUMO中的节点平面解释了在2/7与1位置对替代的不同光物理反应.
- 替代模式是烯衍生物中的光物理性质的关键决定因素,可以为特定应用进行微调.
- 合成的烯衍生物为需要特定光特性的应用提供了潜力,例如先进的光学材料或传感器.
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