The effect of broken conjugation on the excited state: ether linkage in the cyano-substituted poly(p-phenylene vinylene) conjugated polymer poly(2,5,2',5'-tetrahexyloxy-8,7'-dicyano-di-p-phenylene vinylene).

A photoluminescence study of poly(phenylene vinylene) derivatives: The effect of intrinsic persistence length

We report the results of light scattering, absorption, excitation, and emission spectroscopy of three polyphenylene vinylene (PPV) derivatives; poly[Zmethoxy, 5-(2’-ethyl-hexyloxy-p-phenylenevinylene] (MEH-PPV), poly[Zbutoxy, 5-(2’-ethyl-hexyloxy-p-phenylene-vinylene] (BEH-PPV), and poly[2-dicholestanoxy-p-phenylene-vinylene] (BCHA-PPV) in solution with p-xylene. We find that increasing the siz...

The role of long-lived dark states in the photoluminescence dynamics of phenylene vinylene conjugated polymers

The role of intermediate nonluminescent states in the relaxation of singlet excitons in the conjugated polymer poly~phenylene vinylene! ~PPV! and its soluble derivative poly@(2-methoxy-5-hexyloxy-p-phenylene) vinylene# ~MH-PPV! is investigated. Time-resolved luminescence and absorption measurements provide evidence for a long-lived, weakly emissive species in PPV at 17 K, in addition to the lum...

Hole blocking in carbon nanotube–polymer composite organic light-emitting diodes based on poly (m-phenylene vinylene-co-2, 5-dioctoxy-p-phenylene vinylene)

Time domain investigation of the intrachain vibrational dynamics of a prototypical light-emitting conjugated polymer.

Coherent nuclear motion of the carbon backbone is monitored in real time in substituted poly(phenylene)-vinylene in both excited and ground electronic state using sub-10-fs light pulses. Characteristic features of the intrachain vibrational dynamics are obtained. We observe vibrational dephasing in the excited state within 1 ps (time constant T(2e) approximately 300 fs). These findings are in a...

Tight intermolecular packing through supramolecular interactions in crystals of cyano substituted oligo(para-phenylene vinylene): a key factor for aggregation-induced emission.

Strong supramolecular interactions, which induced tight packing and rigid molecules in crystals of cyano substituent oligo(para-phenylene vinylene) (CN-DPDSB), are the key factor for the high luminescence efficiency of its crystals; opposite to its isolated molecules in solution which have very low luminescence efficiency.