Effect of Mesophase Structure on the Intermolecular Triplet Quenching of Photoexcited ZnTPP and CuTPP Mixtures
Effect of Mesophase Structure on the Intermolecular Triplet Quenching of Photoexcited ZnTPP and CuTPP Mixtures
复制标题
中间相结构对光激发 ZnTPP 和 CuTPP 混合物分子间三重态猝灭的影响
DOI：
10.1021/jp961756g
复制
发表时间：
1996
期刊：
影响因子：
--
通讯作者：
H. Levanon
中科院分区：
文献类型：
--
作者：
A. Regev;T. Galili;H. Levanon
本文报道了在几种热致液晶（LC）中取向的光激发Zn-和Cu-四苯基卟啉（TPP）混合物的时间分辨EPR检测。ZnTPP的瞬态三重态EPR谱和CuTPP的双重态基态CW谱都被记录下来，并通过宽温度范围（130 - 370 K）的线形分析进行定量分析。结果表明，ZnTPP的光激发三重态完全猝灭的光激发CuTPP物种排他地在流体近晶相的多域LC（ZLI-1167），而在其他阶段的LC，以及在其他LC（E-7和ZLI-4389）有没有任何迹象表明不同的发色团之间的相互作用。结果被解释为ZnTPP-CuTPP瞬态复合物的形成，这取决于相互作用的发色团的有利的相互取向，特别是由ZLI-1167的近晶相的层和多畴结构所施加的。
Time-resolved EPR detection of photoexcited Zn− and Cu−tetraphenylporphyrin (TPP) mixtures oriented in several thermotropic liquid crystals (LCs) is reported. Both the transient triplet EPR spectra of ZnTPP and the doublet ground state CW spectra of CuTPP were recorded and quantitatively analyzed via line shape analyses over a wide temperature range (130−370 K). It is shown that the photoexcited triplet state of ZnTPP is entirely quenched by the photoexcited CuTPP species exclusively in the fluid smectic phase of a multidomain LC (ZLI-1167), whereas in the other phases of this LC, as well as in other LCs (E-7 and ZLI-4389) there is no indication of any interaction between the different chromophores. The results are interpreted in terms of a ZnTPP−CuTPP transient complex formation, which depends on a favorable mutual orientation of the interacting chromophores, specifically imposed by the layers and multidomain structure of the smectic phase of ZLI-1167.