SURFACE-ENHANCED RAMAN-STUDY OF THE PYRIDINE-IODINE CHARGE-TRANSFER COMPLEX ON THE SILVER ELECTRODE

The surface enhanced Raman spectra (SERS) of the pyridine-iodine charg e transfer complex on the Ag electrode were identified. As compared wi th the well known SERS of pyridine, the nu(1), nu(6a) and nu(12) modes are blue-shifted. This is also confirmed from the comparison of the i nfrared absorption spectra of pyridine-iodine crystalline complex and pyridine. The origin of the blue shift and other characteristics of th e SERS spectra of the complex are discussed. An attempt to observe the SERS spectra of the iodine moiety of the complex was unsuccessful. Th is is attributed to the short range effect of the charge transfer mech anism of SERS.