Deactivation processes of Rhodamine B (RB) in water and interacting with silver sols were studied by using conventional fluorescence, laser-induced fluorescence, and pulsed laser photoacoustics. Results showed that the emission efficiencies, absorption cross sections, and nonradiative deactivation pathway of RB interacting with silver spheroids of different sizes are comparable to those obtained for the dye in aqueous solutions. Copyright 1999 Academic Press.