Fig. 9.

Measured extinction spectra of the silver nanoparticle samples with particle sizes of approximately a 50, b 90 and c 130 nm and calculated theoretical extinction spectra of spherical silver particles with diameters of d 50, e 90 and f 130 nm. The three measured spectra in a–c correspond to different particle coverages. Theoretical spectra in d–f were calculated for single particle using refractive indices of 1.0 and 1.5 and for particle size distribution using a refractive index of 1.0 for the dielectric environment