Authors: M Futamata Y Maruyama
Publish Date: 2007/03/01
Volume: 388, Issue: 1, Pages: 89-102
Abstract
The critical importance of the junction between touching or closely adjacent Ag nanoparticles associated with singlemolecule sensitivity SMS in surfaceenhanced Raman scattering SERS was confirmed via the following observations 1 an additional peak is observed in elastic scattering only for the SERSactive state which originated from absorption of adsorbates 2 local and farfield evaluation using a finite difference time domain method could reproduce this extra peak and anticipate the significantly enhanced field even inside the adsorbates sitting at the junction through an increased coupling of the localized surface plasmons and 3 in addition to enhanced fluorescence of adsorbed dye an inelastic scattering peak was observed and attributed to the metal surface electron Concerning the chemical enhancement in SERS Cl− anions activate the AgClR6G rhodamine samples by inducing intrinsic electronic interaction between Ag and R6G molecules This electronic interaction is irreversibly quenched by the addition of thiosulfate anions which dissolve Ag+ cations while the electromagnetic EM effect remains intactThis research was financially supported in part by GrantinAid for Scientific Research B 17350013 by Japan Society for the Promotion of Science JSPS and by Core Research for Evolutional Science and Technology CREST project in the Japan Science and Technology Agency JST We thank Dr Mitsuru Ishikawa AIST for collaboration
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