SERS EXCITATION PROFILES OF COADSORBED MOLECULES OF O-NITROBENZOIC ACID AND PYRIDINE

It is proposed in this paper that the comparison experiments on SERS excitation profiles of coadsorbed molecules can provide a critical test of the nature of SERS resonance mechanisms. O- nitrobenzoic acid and pyridine coadsorbed on Ag sol have different resonant maxima in their SERS excitation profiles. Unlike usual excitation experiments on SERS, the results show that there must be a non-electromagnetic enhancement mechanism on SERS.