Critical exponents in a percolation picture of the fluorescence quenching during the sol-gel transition
Laboratory of Physicochemistry of Dielectrics and Magnetics, Department of Chemistry, University of Warsaw, 02-089 Warsaw, ul. Żwirki I Wigury 101, Poland
Published online: 15 September 2000
Herewith we report on the measurements of the time evolution of the fluorescence yield and the Rayleigh scattering, performed during the gelation process in the following solutions: gelatin in water, gelatin in a heavy water and agarose in water. Our results provide the experimental evidence of the universal power law, resulting from the percolation theory, which expresses the dependence of the fluorescence yield on the number of intermolecular bonds created during the sol-gel transition. The values of universal critical exponents present in this law are found to have the same values for all investigated materials.
PACS: 82.70.Gg – Gels and sols / 81.20.Fw – Sol gel processing, precipitation / 78.30.-j – Infrared and Raman spectra / 36.40.Vz – Optical properties of clusters
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2000