Surface-plasmon resonances of silver microparticle aerosols have been measured as a function of average particle size. Resonance line shapes are modeled as a function of particle size and complex refractive index. The surface-plasmon frequency is found to exhibit a red shift from 3.8 to 3.4 eV as the average particle diameter is decreased by approximately a factor of 3 in contrast to the blue shift observed for matrix-isolated silver particles.

• Received 15 August 1989

DOI:https://doi.org/10.1103/PhysRevB.40.9982