Excitonic Coupling in Linear and Trefoil Trimer Perylenediimide Molecules Probed by Single-Molecule Spectroscopy

详细信息    查看全文

• 作者：Hyejin Yoo ; Shu Furumaki ; Jaesung Yang ; Ji-Eun Lee ; Heejae Chung ; Tatsuya Oba ; Hiroyuki Kobayashi ; Boris Rybtchinski ; Thea M. Wilson ; Michael R. Wasielewski ; Martin Vacha ; Dongho Kim
• 刊名：The Journal of Physical Chemistry B
• 出版年：2012
• 出版时间：October 25, 2012
• 年：2012
• 卷：116
• 期：42
• 页码：12878-12886
• 全文大小：487K
• 年卷期：v.116,no.42(October 25, 2012)
• ISSN：1520-5207

文摘

Perylenediimide (PDI) molecules are promising building blocks for photophysical studies of electronic interactions within multichromophore arrays. Such PDI arrays are important materials for fabrication of molecular nanodevices such as organic light-emitting diodes, organic semiconductors, and biosensors because of their high photostability, chemical and physical inertness, electron affinity, and high tinctorial strength over the entire visible spectrum. In this work, PDIs have been organized into linear (L3) and trefoil (T3) trimer molecules and investigated by single-molecule fluorescence microscopy to probe the relationship between molecular structures and interchromophoric electronic interactions. We found a broad distribution of coupling strengths in both L3 and T3 and hence strong/weak coupling between PDI units by monitoring spectral peak shifts in single-molecule fluorescence spectra upon sequential photobleaching of each constituent chromophore. In addition, we used a wide-field defocused imaging technique to resolve heterogeneities in molecular structures of L3 and T3 embedded in a PMMA polymer matrix. A systematic comparison between the two sets of experimental results allowed us to infer the correlation between intermolecular interactions and molecular structures. Our results show control of the PDI intermolecular interactions using suitable multichromophoric structures.