Structure-Dependent Photophysics of First-Generation Phenyl-Cored Thiophene Dendrimers
Structure-Dependent Photophysics of First-Generation Phenyl-Cored Thiophene Dendrimers
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DOI：
10.1021/cm802410d
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发表时间：
2009-01
影响因子：
8.6
通讯作者：
W. Mitchell;A. Ferguson;M. Köse;B. L. Rupert;D. Ginley;G. Rumbles;S. Shaheen;N. Kopidakis
中科院分区：
文献类型：
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作者：
W. Mitchell;A. Ferguson;M. Köse;B. L. Rupert;D. Ginley;G. Rumbles;S. Shaheen;N. Kopidakis
我们已经制备了两个系列的第一代噻吩桥树枝状聚合物，具有三个（3G 1）或四个（4G 1）臂连接到苯基核心，以阐明它们的结构-性能关系。结合稳态和时间分辨光谱技术的光学性质进行了研究。3-臂树枝状聚合物的稳态光谱数据表明，激子在α-共轭噻吩片段和苯基核上离域，但树枝状分子的间位连接阻止了它们的电子通信。相比之下，在4臂树枝状聚合物中允许通过核心与邻位和帕拉的树枝状分子缀合，尽管数据表明缀合长度不延伸超过两个偶联树枝状分子的α-缀合部分的全长。这一观察结果是由于相邻臂之间的空间相互作用，这迫使臂扭曲和弯曲出苯基核的平面，并且在破坏...
We have prepared two series of first-generation thiophene-bridge dendrimers, with either three (3G1) or four (4G1) arms attached to a phenyl core, to elucidate their structure−property relationships. Optical properties were investigated with a combination of steady-state and time-resolved spectroscopic techniques. Steady-state spectroscopic data for the 3-arm dendrimers suggests that the exciton is delocalized over the α-conjugated thiophene segment and the phenyl core, but that the meta-linking of the dendrons prevents their electronic communication. In contrast, conjugation through the core to dendrons in the ortho and para positions is permitted in the 4-arm dendrimers, although the data suggest that the conjugation length does not extend over the full length of the α-conjugated sections of two coupled dendrons. This observation is due to steric interactions between neighboring arms, which forces the arms to twist and bend out of the plane of the phenyl core, and is particularly prevalent in disrupting...