SURFACE-ENHANCED RESONANT RAMAN-SPECTRA OF PERYLENETETRACARBOXYLIC DERIVATIVES ON SILVER COLLOIDS AND ISLAND FILMS

The surface-enhanced resonant Raman scattering (SERRS) of Ferylenetetr acarboxylic derivatives obtained on colloidal silver and on silver isl and films is reported. The molecular adsorption onto the metal colloid is very slow, the Raman bands have a narrow bandwidth and the spectra l data are characteristic of physical adsorption. The study includes N -hexyl perylenetetracarboxylic monoimide (HPTCO), N-butyl peryienetetr acarboxylic diimide (BPTCNH), N-isobutyl perylenetetracarboxylic diimi de (IBPTCNH) and N-pentyl perylenetetracarboxylic diimide (PPTCNH). Th e assignment of the characteristic normal modes and the spectroscopic characterization of PTCNH materials were carried out using Fourier tra nsform IR (FTIR) spectra of KBr pellets, resonant Raman scattering (RR S) spectra and electronic absorption and fluorescence spectra. (C) 199 7 Elsevier Science B.V.