卤代苯溶剂对镓咔咯配合物光物理性质的影响:外重原子效应

Influence of Halogenated Benzene Solvents on the Photophysical Properties of Gallium Corroles: the External Heavy Atom Effect

利用紫外-可见光谱、稳态和时间分辨荧光光谱以及飞秒瞬态吸收光谱探测了不同卤代苯溶剂对三种五氟苯基取代的镓咔咯(1-Ga、2-Ga、3-Ga)光物理性质的影响,结果表明卤代苯溶剂的色散力对于镓咔咯电子光谱吸收峰位置的影响起着主要作用;溶剂外重原子效应能显著降低镓咔咯的荧光量子产率。飞秒瞬态吸收光谱表明,光激发下,镓咔咯与卤代苯溶剂之间可发生电子转移反应,溶剂的重原子效应可以减缓电荷分离态复合物电荷重组速率。

The photophysical properties of pentafluorophenyl-substituted gallium corroles in halogenated benzenes were investigated using ultraviolet-visible（UV-Vis）, steady-state, time-resolved fluorescence, and femtosecond transient absorption spectroscopies. The results showed that the absorption maximum wavelength of the gallium corroles was mainly related to the dispersion force of the halogenated benzene solvents. The external heavy atom effect of halogenated benzenes may markedly lower the fluorescence quantum yield of gallium corrole complexes. Photoinduced electron transfer between the gallium corroles and halogenated benzene solvents was detected by femtosecond transient absorption spectroscopy. The experimental evidence showed that the heavy atom effect of the solvent might lower the charge recombination rate of charge-separated gallium corrole-solvent complexes.