SURFACE-ENHANCED RAMAN-SPECTRA OF PYRIDINE AND PYRAZINE ADSORBED ON AAU(210) SINGLE-CRYSTAL ELECTRODE

Surface-enhanced Raman scattering (SERS) spectra of pyrazine and pyrid ine adsorbed on an ''unroughened'' Au(210) electrode surface have been obtained for the first time. The SERS spectra indicate that both pyri dine and pyrazine adsorb on the Au(210) electrode via their nitrogen l one pairs (end-on configuration). The integrated SERS intensities from the ring-breathing vibrations (ca. 1010 cm(-1) for pyridine and 1019 cm(-1) for pyrazine) were measured. The potential profiles (integrated SERS intensity versus potential plots) were compared to the surface c overage data, obtained electrochemically, for the adsorption of pyridi ne and pyrazine on Au(210). No simple relationship was found between t he SERS intensities and the surface coverage data; however, it seems t hat the SERS intensities track the surface coverage for low surface co ncentrations (less than a monolayer).