Surface plasmon resonances in strongly coupled gold nanosphere chains from monomer to hexamer.

We present experimental data on the light scattering properties of linear chains of gold nanoparticles with up to six nanoparticles and an interparticle spacing of 1 nm. A red shift of the surface plasmon resonance with increasing chain length is observed. An exponential model applied to the experimental data allows determination of an asymptotic maximum resonance at a chain length of 10-12 particles. The optical data are compared with analytical and numerical calculation methods (EEM and BEM).