Encontrados 8 documentos, a visualizar página 1 de 1
A resonance Rayleigh scattering study of unlabeled and pyrene-labeled poly(acry...
Costa, Telma; Seixas de Melo, J.http://www.sciencedirect.com/science/article/B6TGS-4TVTK04-4/2/52a09901f70ff2c94360af23956381c5
On the triplet state of poly(N-vinylcarbazole)
Pina, J.; Seixas de Melo, J.; Burrows, H. D.; Monkman, A. P.; Navaratnam, S.Triplet state properties including transient triplet absorption spectrum, intersystem crossing yields in solution at room temperature and phosphorescence spectra, quantum yields and lifetimes at low temperature as well as singlet oxygen yields were obtained for poly(N-vinylcarbazole) (PVK) in 2-methyl-tetrahydrofuran (2-MeTHF), cyclohexane or benzene. The results allow the determination of the energy value for ...
The effect of substitution and isomeric imperfection on the photophysical behav...
Seixas de Melo, J.; Pina, J.; Burrows, H. D.; Brocke, S.; Herzog, O.; Thorn-Csányi, E.Spectroscopic and photophysical properties of two p-phenylenevinylene (PV) trimers, 2,5-substituted diheptyl-(p-phenylenevinylene) and di-[(2-ethylhexyl)oxy]-(p-phenylenevinylene), were studied using absorption spectroscopy, fluorescence and laser flash photolysis. The change from alkyl to alkyloxy groups red-shifts the absorption and fluorescence bands. The rate of internal conversion is independent of the sub...
Hole formation and transfer in poly[9,9-di(ethylhexyl)fluorene] and an amine en...
Burrows, H. D.; Seixas de Melo, J.; Forster, M.; Güntner, R.; Scherf, U.; Monkman, A. P.; Navaratnam, S.Pulse radiolysis has been used to study the positively charged state of isolated chains of poly[9,9-di(ethylhexyl)fluorene] in chloroform solution. This is found to have an absorption maximum at 560 nm and a weaker band around 420 nm. Intermolecular electron transfer is observed from the aromatic amine tri(p-tolylamine) to this species. With the corresponding polyfluorene derivative end-capped by an arylamine, ...
Triplet state dynamics on isolated conjugated polymer chains
Burrows, H. D.; Seixas de Melo, J.; Serpa, C.; Arnaut, L. G.; Miguel, M. da G.; Monkman, A. P.; Hamblett, I.; Navaratnam, S.http://www.sciencedirect.com/science/article/B6TFM-46MD9J0-5/1/ad58ae25c92bd62f507ea5a6a04f467d
Heavy-atom effects on metalloporphyrins and polyhalogenated porphyrins
Azenha, Emília G.; Serra, Arménio C.; Pineiro, Marta; Pereira, Mariette M.; Seixas de Melo, J.; Arnaut, Luis G.; Formosinho, Sebastião J.http://www.sciencedirect.com/science/article/B6TFM-45PTWJX-J/1/69780b458d5289db997df5735c97350c
Switching from intramolecular energy transfer to intramolecular electron transf...
Albelda, M. Teresa; Díaz, Pilar; García-España, Enrique; Lima, João C.; Lodeiro, Carlos; Seixas de Melo, J.; Jorge Parola, A.; Pina, Fernandohttp://www.sciencedirect.com/science/article/B6TFN-44SKJK4-4/1/7cd5958d3acd1757d2b3a88517f1d557
Spectroscopy and photophysics of 4- and 7-hydroxycoumarins and their thione ana...
Seixas de Melo, J.; Fernandes, P. F.Acid-base equilibria were studied for 4-hydroxycoumarin, 7-hydroxy-4-methylcoumarin and their thione derivatives in different media for their ground and lowest energy singlet and triplet excited states. The ethoxylated and/or methoxylated derivatives were also investigated. Characterization involves fluorescence spectra, quantum yields, lifetimes, phosphorescence spectra, lifetimes, and triplet-triplet absorpti...
| Financiadores do RCAAP | |||||||
|
|
|
|
|
|
||