A cluster of six nanoparticles was analyzed with similar results. The use of EELS unveiled bright and dark plasmon modes. The low-energy ones are located on the extremes of the long axis and the high-energy ones on the short axis. The sharper areas of the cluster present higher intensity in the resonance peak. The results presented in this manuscript contribute to the design of plasmonic circuits by metal nanoparticle paths. Authors’ information CDE is a Ph. D. student at the Universidad de Cádiz. WS is a Research
scientist at the Stuttgart Center for Electron Microscopy (StEM), Max Plank Institute for intelligent systems, PAvA is head of the Stuttgart Center for Electron Microscopy
(StEM), Max Planck Institute for intelligent systems. SIM is a full professor at the Departamento de Ciencia de los Materiales e Ingeniería Metalúrgica y Química Inorgánica, see more Universidad de Cádiz. Acknowledgments This work was supported by the Spanish MINECO (projects TEC20011-29120-C05-03 and CONSOLIDER INGENIO 2010 CSD2009-00013) and the Junta de Andalucía (PAI research group TEP-946 INNANOMAT). We would like to thank Giovanni Scavello for helping us on the layout of the figures. References 1. Maier SA: Plasmonics: Fundamentals and Applications. 1st edition. New York: Springer; 2007. 2. Duan HG, 5-Fluoracil in vivo Fernandez-Dominguez AI, Bosman M, Maier SA, Yang JKW: Nanoplasmonics: Epothilone B (EPO906, Patupilone) classical down to the nanometer scale. Nano Lett 2012, 12:1683–1689.CrossRef 3. Barrow SJ, Funston BV-6 AM, Gomez DE, Davis TJ, Mulvaney P: Surface plasmon resonances in strongly coupled gold nanosphere chains from monomer to hexamer. Nano Lett 2011, 11:4180–4187.CrossRef 4. Warner MG, Hutchison JE: Linear assemblies of nanoparticles electrostatically organized on DNA scaffolds. Nat Mater 2003, 2:272–277.CrossRef 5. Woehrle GH, Warner MG, Hutchison JE: Molecular-level
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