Monodisperse Glassy-Nematic Conjugated Oligomers with Chemically Tunable Polarized Light Emission

Journal Article · Sat Oct 11 04:00:00 EDT 2003 · Chemistry of Materials

DOI:https://doi.org/10.1021/cm034579m· OSTI ID:821201

Geng, Y ^[1]; Chen, A C.A.; Ou, J J; Chen, S H; Klubek, K; Vaeth, K M; Tang, C W

---

1. Laboratory for Laser Energetics, University of Rochester, Rochester, NY

A novel series of monodisperse conjugated oligomers were synthesized by inserting varied segments into blue-emitting oligofluorenes to complete the color gamut of light emission. Quantum mechanical calculations revealed that the electron transition dipoles lie largely parallel to the long molecular axes of the central segments responsible for light emission. The orientational order parameter characterizing molecular alignment in thermally processed glassy-nematic films was evaluated at 0.77 to 0.87 by UV-vis absorption dichroism. With an emission dichroic ratio ranging from 9.4 to 13.7, polarized photoluminescence provided further evidence that the long molecular axes are aligned with the nematic director. Polarized organic light-emitting diodes (OLEDs) comprising selected materials resulted in red and yellowish green light emission with dichroic ratios of 14.4 and 18.0 and luminance yields of 0.51 and 5.91 cd/A, respectively. These two sets of data represent the best performance to date of red and green polarized OLEDs.

• Research Organization: Laboratory for Laser Energetics (US)
• Sponsoring Organization: (US)
• DOE Contract Number: FC03-92SF19460
• OSTI ID: 821201
• Report Number(s): DOE/Sf-19460-506; 1409; 2003-153
• Journal Information: Chemistry of Materials, Journal Name: Chemistry of Materials Journal Issue: 23 Vol. 15
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
COLOR
DICHROISM
LIGHT EMITTING DIODES
ORDER PARAMETERS
ORGANIC FLUORINE COMPOUNDS
PERFORMANCE
PHOTOLUMINESCENCE
SYNTHESIS