A SURFACE PHASE TRANSITION MONITORED USING SURFACE-ENHANCED RAMAN SCATTERING

Abstract

We report the surface-enhanced Raman spectra for several molecules adsorbed on aqueous silver colloids. Of particular interest is evidence that para-aminobenzoic acid exists on the colloidal particle surface in two different phases. The first phase corresponds to a solid and the second phase to vapor in the model proposed to explain the spectra. The model is based on the changes observed in the spectra as a result of variation of temperature and concentration.