title: High spatial resolution mapping of individual and collective localized surface plasmon resonance modes of silver nanoparticle aggregates: correlation to optical measurements.
abstract: Non-isolated nanoparticles show a plasmonic response that is governed by the localized surface plasmon resonance (LSPR) collective modes created by the nanoparticle aggregates. The individual and collective LSPR modes of silver nanoparticle aggregated by covalent binding by means of bifunctional molecular linkers are described in this study. Individual contributions to the collective modes are investigated at nanometer scale by means of energy-filtering transmission electron microscopy and compared to ultraviolet-visible spectroscopy. It is found that the aspect ratio and the shape of the clusters are the two main contributors to the low-energy collective modes.
authors.affiliation: Instituto de Microscopía Electrónica y Materiales, Departamento de Ciencia de los Materiales e I. M. y Q. I., Facultad de Ciencias, Universidad de Cádiz, Campus Río San Pedro, s/n, 11510, Puerto Real, Cádiz, Spain, carlos.diazegea@uca.es.
authors.forename: Carlos
authors.initials: C
authors.lastname: Diaz-Egea
authors.forename: Rafael
authors.initials: R
authors.lastname: Abargues
authors.forename: Juan P
authors.initials: JP
authors.lastname: Martínez-Pastor
authors.forename: Wilfried
authors.initials: W
authors.lastname: Sigle
authors.forename: Peter A
authors.initials: PA
authors.lastname: van Aken
authors.forename: Sergio I
authors.initials: SI
authors.lastname: Molina