Surface enhanced spectroscopy of perylene derivatives

Surface enhanced Raman (SERS), surface enhanced Resonance Raman (SERRS) of mono and multilayer films of three N,N{dollar}spprime{dollar}-unsymmetrical dialkyl-3,4:9,10-perylenebis (dicarboximides)s, namely N-octyl-3,4:9,10-perylenetetracarboxylic monoanhydride(Oc-PTCDO), N-octyl-3,4:9,10-perylenetetracarboxylic monoimide(Oc-PTCDNH) and N-octyl, N{dollar}spprime{dollar}-isobutyl-3,4:9,10-perylene-bis (dicarboximide) (PBDC) have been studied and vibrational analyses have been attempted. SERS and SERRS of evaporated thin films of perylene, 3,4:9,10 perylene tetracarboxylic dianhydride (PTCDA) and 3,4:9,10 perylene tetracarboxylic N,N{dollar}spprime{dollar} bis (methyl) diimide (PTCDIMe) on tin sphere, Ag island and Au island films are used to characterize the vibrations of the three unsymmetrical perylene derivatives. It was concluded that the LB layers were physisorbed onto the SERS active surfaces.; All three samples form aggregates due to intermolecular interactions within a single Langmuir Blodgett (LB) layer. Fluorescence signal of aggregate (excimer) is stronger in a neat layer whereas in a mixed layer (perylene derivative: arachidic acid) monomer emission is the dominant one. (Abstract shortened by UMI.)...