Physics – Condensed Matter – Soft Condensed Matter
Scientific paper
2001-12-29
Physics
Condensed Matter
Soft Condensed Matter
5 pages, 4 figures
Scientific paper
10.1103/PhysRevLett.88.197401
We have measured the ratio, r = $\sigma_S/\sigma_T$ of the formation cross section, $\sigma$ of singlet ($\sigma_S$) and triplet ($\sigma_T$) excitons from oppositely charged polarons in a large variety of $\pi$-conjugated oligomer and polymer films, using the photoinduced absorption and optically detected magnetic resonance spectroscopies. The ratio r is directly related to the singlet exciton yield, which in turn determines the maximum electroluminescence quantum efficiency in organic light emitting diodes (OLED). We discovered that r increases with the conjugation length, CL; in fact a universal dependence exists in which $r^{-1}$ depends linearly on $CL^{-1}$, irrespective of the chain backbone structure. These results indicate that $\pi$-conjugated polymers have a clear advantage over small molecules in OLED applications.
Janssen R. A. J.
Jiang X. M.
Vardeny Valy Z.
Wohlgenannt Michael
No associations
LandOfFree
Conjugation-Length Dependence of Spin-Dependent Exciton Formation Rates in Pi-Conjugated Oligomers and Polymers does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Conjugation-Length Dependence of Spin-Dependent Exciton Formation Rates in Pi-Conjugated Oligomers and Polymers, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Conjugation-Length Dependence of Spin-Dependent Exciton Formation Rates in Pi-Conjugated Oligomers and Polymers will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-95455