The SERS phenomenon in light of recent excitation profile measurements

We have recently reported on the measurements of the ultra high vacuum (UHV) surface enhanced Raman scattering (SERS) excitation profile for pyridine and CO on two different kinds of silver surfaces prepared in situ (ref.1). The curves all show a maximum and the peak positions depend both on the adsorbed molecule and the preparation of the silver surface. The optical spectra of these systems have also been measured using an oscillating beam spectrometer which compares the difference in the reflected light at two adjacent areas with and without the adsorbed molecules. The SERS phenomenon investigated in UHV is viewed in light of these results.