Structural and Optical Properties of Self-AssembledChains of Plasmonic Nanocubes.

Solution-based linearself-assembly of metal nanoparticles offersa powerful strategy for creating plasmonic polymers, which, so far,have been formed from spherical nanoparticles and cylindrical nanorods.Here we report linear solution-based self-assembly of metal nanocubes(NCs), examine the structural characteristics of the NC chains, anddemonstrate their advanced optical characteristics. In comparisonwith chains of nanospheres with similar dimensions, composition, andsurface chemistry, predominant face-to-face assembly of large NCscoated with short polymer ligands led to a larger volume of hot spotsin the chains, a nearly uniform E-field enhancement in the gaps betweencolinear NCs, and a new coupling mode for NC chains due to the formationof a Fabry–Perot resonatorstructure formed by face-to-face bonded NCs. The NC chains exhibitedstronger surface-enhanced Raman scattering in comparison with linearassemblies of nanospheres. The experimental results were in agreementwith finite difference time domain simulations. [ABSTRACT FROM AUTHOR]