Surface enhanced Raman study of the pyridine—iodine charge transfer complex on the silver electrode

Abstract

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