Intra- and Intermolecular Photochemical Properties of Poly(amidoamine) Dendrons with an Anthracene at Focal Point
Intra- and Intermolecular Photochemical Properties of Poly(amidoamine) Dendrons with an Anthracene at Focal Point
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焦点为蒽的聚酰胺胺树突的分子内和分子间光化学性质
DOI：
10.1246/bcsj.76.743
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发表时间：
2003
影响因子：
4
通讯作者：
H. Aoyama
中科院分区：
文献类型：
--
作者：
M. Fujitsuka;O. Ito;Y. Takaguchi;T. Tajima;K. Ohta;J. Motoyoshiya;H. Aoyama
用稳态和暂态光谱方法研究了聚酰胺胺类树枝的光物理和光化学性质。高世代树突(G3.5)中的菲部分的荧光寿命略短于低世代同系物(G0.5)。另一方面，G3.5的三重态寿命比G0.5长。蒽基树枝G3.5和G0.5的三重态向O2(KO2)转移能量的双分子速率常数和T-T湮没速率常数(KTT)几乎相同，表明树枝基团不阻碍O2或菲部分的接近.G3.5的光解离速率与G0.5的光解离速率相似，而这些菲二聚体的光解离速率按菲>；G0.5>；G3.5的顺序递增，表明树枝状楔形分子之间存在一定的引力。
Photophysical and photochemical properties of poly(amidoamine) dendrons containing an anthracene at the focal point have been studied by the steady-state and transient spectroscopic methods in solution. The fluorescence lifetime of the anthracene moiety in the higher generation dendron (G3.5) is slightly shorter than that of the lower generation homologue (G0.5). On the other hand, the triplet lifetime of G3.5 is longer than that of G0.5. The bimolecular rate constants for energy transfer from the triplet states of the anthracene moiety to O2 (kO2) and for T–T annihilation (kTT) were almost the same for the anthryl dendrons, G3.5 and G0.5, suggesting that the dendron groups do not hinder the approach of O2 or the anthracene moiety. Photodimerization of G3.5 took place at a similar rate to G0.5, while the photodissociation rates of these anthracene dimers increase in the order of anthracene > G0.5 > G3.5, suggesting the presence of some attractive forces between dendron wedges.