title: Plasmon interactions between gold nanoparticles in aqueous solution with controlled spatial separation.
abstract: The effects of interparticle distance on the UV-visible absorption spectrum of gold nanocrystals aggregates in aqueous solution have been investigated. The aggregates were produced by ion-templated chelation of omega-mercaptocarboxylic acid ligands covalently attached to the nanoparticles surface. Variation of the ligand chain length provides control over the interparticle separation in the aggregates. The UV-visible spectra consist typically of a single particle band and a secondary band at higher wavelengths associated with the formation of aggregates in solution. The position of the latter depends on interparticle separation up to distances of approximately 8 nm, in accordance with existing models. Potential applications therefore include distance sensitive labels or proximity probes. Conversely, variation of the ligand length allows the preparation of nanostuctured materials with tuned optical properties.
authors.affiliation: Centre for Nanoscale Science, Chemistry Department, University of Liverpool, Liverpool, UKL69 7ZD.
authors.forename: Iuliana E
authors.initials: IE
authors.lastname: Sendroiu
authors.forename: Stijn F L
authors.initials: SF
authors.lastname: Mertens
authors.forename: David J
authors.initials: DJ
authors.lastname: Schiffrin
mesh_terms: D003460:Crystallization; D006046:Gold; D008854:Microscopy, Electron; D008958:Models, Molecular; D049329:Nanostructures; D013059:Spectrum Analysis, Raman; D013438:Sulfhydryl Compounds / Q000737:chemistry*
chemical_list: D013438:Sulfhydryl Compounds; D006046:Gold