@article {28611,
	title = {Intramolecular Interactions of Highly π-Conjugated Perylenediimide Oligomers Probed by Single-Molecule Spectroscopy},
	journal = {J. Phys. Chem. Lett.},
	volume = {5},
	number = {21},
	year = {2014},
	month = {2014 NOV 6},
	pages = {3895-3901},
	type = {Article},
	abstract = {Highly pi-conjugated perylenediimide (PDI) oligomers are promising low band gap organic materials for various applications in optoelectronics. In this work, individual fluorescence dynamics of ethynylene- and butadiynylene-bridged dimeric and trimeric PDIs (PEP, PBP, and PEPEP) were monitored and analyzed by single-molecule fluorescence spectroscopy to gain information on the degree of extension of pi-conjugation through the acetylene bridge in PDI multichromophores. The simultaneous measurements of fluorescence intensity, lifetime, and spectrum indicate a sequential decrease in pi-conjugation upon photobleaching of PDI monomer units. Furthermore, Huang-Rhys (HR) factors, S, are obtained to evaluate the degree of electronic coupling in view of pi-conjugation and overall rigidity between the PDI units in PDI oligomers at the single-molecule level. In addition, butadiynylene-bridged dimeric PDI (PBP) reveals conformational heterogeneity due to the long butadiynylene linker. These results suggest a new way to control the photophysical properties of the PDI multichromophoric system by expansion of pi-conjugation and modification with different linker groups.[GRAPHICS]},
	isbn = {1948-7185},
	url = {https://pubs.acs.org/doi/pdf/10.1021/jz501765x},
	author = {Cho, JaeWon and Yoo, Hyejin and Lee, JiEun and Yan, Qifan and <strong>Zhao, Dahui*</strong> and Kim, Dongho*}
}
