Surface-enhanced resonance Raman scattering of adsorbates under liquid nitrogen

We compare the room temperature surface-enhanced resonance Raman scattering (SERRS) spectra of three molecules (riboflavin, 1-nitropyrene. and rhodami ne 6G) adsorbed on rough silver films with SERRS spectra of the same sample s submerged in liquid nitrogen. We find that the spectra obtained in the li quid nitrogen environment exhibit substantially higher signal-to-noise rati os, which we attribute to an increase in the SERRS electromagnetic enhancem ent factor in the liquid nitrogen environment arising from the dielectric p roperties of liquid nitrogen. (C) 2001 Published by Elsevier Science B.V.