Exciton Migration in Multi-Stranded Perylene Bisimide J-Aggregates.
Exciton Migration in Multi-Stranded Perylene Bisimide J-Aggregates.
复制标题
DOI：
10.1021/acs.jpclett.0c01669
复制
发表时间：
2020-07
期刊：
影响因子：
--
通讯作者：
Chris Rehhagen;M. Stolte;Stefanie Herbst;Markus Hecht;S. Lochbrunner;F. Würthner;F. Fennel
中科院分区：
文献类型：
--
作者：
Chris Rehhagen;M. Stolte;Stefanie Herbst;Markus Hecht;S. Lochbrunner;F. Würthner;F. Fennel
染料分子自组装超分子系综中激子的迁移受相邻位置间的电子耦合、激发的离域以及堆积排列的控制。在这里，我们把重点放在包装结构和分析激子迁移在两个基于二萘嵌苯双酰亚胺的J-聚集体组成的几乎相同的分子积木，但形成双链与四链滑移堆叠超分子架构。用基于非相干转移的激子-激子湮灭动力学模型分析了激子密度对超快瞬态吸收谱的影响，结果表明，这种迁移是准一维的.通过有利的几何结构增强了迁移距离。我们发现一个因素之间的扩散长度为188 nm和77 nm的双和四链系统的两个以上。超分子设计有效地影响了激子的迁移率，微小的结构变化似乎对染料聚集体的功能性质有显著的影响。
Exciton migration in self-assembled supramolecular ensembles of dye molecules is controlled by the elec-tronic coupling between adjacent sites, the delocalization of the excitation and thereby by the packing ar-rangement. Here, we put emphasis on the packing structure and analyze the exciton migration in two perylene bisimide-based J-aggregates composed of almost identical molecular building blocks but form double- versus quadruple strand slip-stacked supramolecular architectures. Analyzing ultrafast transient absorption spectra in dependence on the exciton density by a kinetic model for exciton-exciton annihila-tion based on incoherent transfer demonstrates that the migration is quasi one-dimensional. The migration distance is enhanced by a beneficial geometrical structure. We find a factor of more than two between the diffusion lengths of 188 nm and 77 nm for the double- and quadruple-stranded system. The supramolecu-lar design efficiently influences the exciton mobility and minor structural changes seem to have a pro-nounced influence on functional properties of dye aggregates.