Hybrid materials consisting of silver nanoparticles and thin films of cyan dyes have been investigated by means of scanning electron microscopy and absorption and fluorescence spectroscopy. It is detected that the molecular absorption and fluorescence of the dye become stronger in the presence of Ag nanoparticles, and that the plasmon absorption band in the silver nanoparticles shifts. The mutual modification of the optical properties of the components of the hybrid materials is explained by the dependence of the plasmon frequency on the permittivity of the surrounding substance and by the influence of the near fields of the silver nanoparticles on the dye molecules. Photoinduced transformations have been studied in organic thin films in the presence of Ag nanoparticles. It is established that the change of the optical density of a dye layer with nanoparticles during irradiation exceeds the analogous changes in a dye layer without nanoparticles by a factor of 10.
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