title: Synthesis and Linear and Nonlinear Optical Properties of Three Push-Pull Oxazol-5(4H)-one Compounds.
abstract: Three uncharged push-pull oxazol-5(4H)-ones were synthesized and thoroughly characterized. The examined molecules contained electron-donor and electron-acceptor groups interacting via a π-conjugated bridge. Spectral properties of the oxazol-5(4H)-ones were studied in detail in three solvents of different polarities. The results indicate a solvatochromic shift toward lower energy for the charge-transfer state. The compounds are weakly fluorescent in polar solvents, but they have high fluorescence quantum yields in nonpolar solvents. Their two-photon absorption (2PA) properties were characterized by the open- and closed-aperture Z-scan technique, by the pump-probe technique, and by the two-photon excited fluorescence method. The dyes exhibit relatively high effective two-photon absorption cross sections ranging from 490 to 2600 GM at ~100 GW/cm(2), according to the Z-scan results, which are found, however, to contain significant contribution from higher-order absorption processes. In addition, these compounds display good photostability.
authors: University of Technology and Life Sciences , Faculty of Chemical Technology and Engineering, Seminaryjna 3, 85-326 Bydgoszcz, Poland.
authors: Beata
authors: B
authors: Jędrzejewska
authors: Wroclaw University of Technology , Faculty of Chemistry, Advanced Materials Engineering and Modelling Group, Wybrzeże Wyspiańskiego 27, 50-370 Wroclaw, Poland.|Laboratory of Biology and Applied Pharmacology, CNRS, Ecole Normale Superieure de Cachan , 61 Avenue du President Wilson, 94235 Cachan, France.
authors: Marta
authors: M
authors: Gordel
authors: Wroclaw University of Technology , Faculty of Chemistry, Advanced Materials Engineering and Modelling Group, Wybrzeże Wyspiańskiego 27, 50-370 Wroclaw, Poland.
authors: Janusz
authors: J
authors: Szeremeta
authors: Nicolaus Copernicus University , Collegium Medicum, Department of Physical Chemistry, Kurpińskiego 5, 85-950 Bydgoszcz, Poland.
authors: Przemysław
authors: P
authors: Krawczyk
authors: Wroclaw University of Technology , Faculty of Chemistry, Advanced Materials Engineering and Modelling Group, Wybrzeże Wyspiańskiego 27, 50-370 Wroclaw, Poland.
authors: Marek
authors: M
authors: Samoć