Optical properties of star-shaped gold nanoparticles.

Here we report the synthesis, structure, and optical properties of ca. 100 nm star-shaped gold nanoparticles. Single particle spectroscopy measurements revealed that these nanoparticles have multiple plasmon resonances resulting in polarization-dependent scattering with multiple spectral peaks, which correspond to the different tips on the star-shaped structure. The plasmon resonances were also found to be extremely sensitive to the local dielectric environment.