Picosecond time-resolved dual fluorescence, transient absorption and reorientation time measurements of push-pull diphenyl-polyenes: Evidence for 'loose' complex and 'bicimer' species
| Autor: | Jean Oberle, Claude Rullière, Emmanuel Abraham, R. Lapouyade, Gediminas Jonusauskas, Kaoru Minoshima |
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| Přispěvatelé: | Centre de physique moléculaire optique et hertzienne (CPMOH), Université Sciences et Technologies - Bordeaux 1-Centre National de la Recherche Scientifique (CNRS), Institut de Chimie de la Matière Condensée de Bordeaux (ICMCB), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut Polytechnique de Bordeaux-Université de Bordeaux (UB) |
| Jazyk: | angličtina |
| Rok vydání: | 1997 |
| Předmět: |
[PHYS]Physics [physics]
[PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics] Chemistry Streak camera Analytical chemistry General Physics and Astronomy 02 engineering and technology 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences Molecular physics Fluorescence 3. Good health 0104 chemical sciences Excited state Picosecond Ultrafast laser spectroscopy Physical and Theoretical Chemistry 0210 nano-technology Ground state Absorption (electromagnetic radiation) Excitation |
| Zdroj: | Chemical Physics Chemical Physics, Elsevier, 1997, 219 (1), pp.73-89. ⟨10.1016/S0301-0104(97)00091-8⟩ |
| ISSN: | 0301-0104 |
| DOI: | 10.1016/S0301-0104(97)00091-8⟩ |
| Popis: | International audience; Picosecond streak camera measurements, time-resolved absorption and reorientation time measurements (by optical Kerr effect) of push-pull diphenyl-polenes (4-dimethylamino 4′-cyano stilbene: DCS, 1-(p-N,N-dimethylamino)-4-(p-cyanophenyl)-1,3-butadiene: DCB) in solution have revealed, in polar solvents at high concentration and high excitation intensity, the presence of a new emitting species characterized by an anomalous red-shifted fluorescence band. The formation rate and decay excited state decay time of the new species is measured for the first time at room temperature as well as the spectral characteristics of the fluorescence. The intensity of the new fluorescence band has been found to be proportional to the square of the excitation intensity. Furthermore, the reorientation time at high concentration has been determined to be nearly twice as long as that at low concentration, indicating the possibility of the formation of complexes in the ground state with nearly twice the molecular volume compared with the monomer. This bimolecular and biphotonic process, demonstrated by the experimental results, makes it possible to reveal a ‘loose’ complex formation in the ground state, leading upon high excitation intensity to the new emitting species already called ‘bicimer’ in preliminary studies and formed by the association of two electronically excited molecules. |
| Databáze: | OpenAIRE |
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