Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
10618721 | Synthetic Metals | 2005 | 4 Pages |
Abstract
We present the excited state dynamics of the low band gap alternating polyfluorene copolymer, DiO-PFDTBT. The copolymer structure is an alternating sequence of donor and acceptor units consisting of 9,9-dioctyl-9H-fluorene and 4,7-di-thiophen-2-yl-benzo[1,2,5]thiadiazolyl units. Calculations have predicted that the first excited state has charge transfer character, while the second strongly allowed excited state is a delocalized Ï-conjugated state. We show that the excited state dynamics involves internal conversion (IC) from the second strongly allowed excited state to the first excited state. Furthermore, excitation energy transfer (EET) on the â¼1-10Â ps time scale is observed as well as a subsequent formation of a stabilized long-lived emissive state, which has a decay time of 3.25Â ns. The origin of this stabilized state is discussed in relation to the intrinsic charge transfer nature of the DiO-PFDTBT.
Related Topics
Physical Sciences and Engineering
Materials Science
Biomaterials
Authors
Kim G. Jespersen, Arkady Yartsev, Thorbjörn Pascher, Villy Sundström,