SURFACE-ENHANCED FLUORESCENCE AND SERRS SPECTRA OF N-OCTADECYL-3,4 9,10-PERYLENETETRACARBOXYLIC MONOANHYDRIDE ON SILVER ISLAND FILMS/

The Langmuir-Blodgett (LB) technique has been used to fabricate monola yers of N-octadecyl-3,4:9,10-perylenetetracarboxylic monoanhydride mon oimide (OD-PTCO) on infrared transparent windows, glass and silver isl and substrates. The long alkyl chain CH3-(CP2)(17)-PTCO, a perylene de rivative with a low quantum yield, was specially synthesized for the s tudy of the electromagnetically surface-enhanced fluorescence (SEF). I t is shown that lame enhancement factors for SEF (>10) are obtained fo r OD-PTCO LB films deposited on silver island films of 6, 10 and 14 nm mass thickness. The three-dimensional images of the silver island fil ms used to produce surface-enhanced spectra were obtained by atomic fo rce microscopy. The delicate interplay between energy transfer and ele ctromagnetic enhancement are illustrated by spectra containing the sur face-enhanced resonant Raman scattering and SEF effects in the same sp ectral region. The infrared and resonance Raman scattering spectra of the bulk and LB films are also reported. (C) 1997 Elsevier Science B.V .