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05:52
Observation and Analysis of Blinking Surface-enhanced Raman Scattering
Published on: January 11, 2018
Localized surface plasmon resonance spectroscopy near molecular resonances
Amanda J Haes1, Shengli Zou, Jing Zhao
1Department of Chemistry, Northwestern University, Evanston, Illinois 60208-3113, USA.
Journal of the American Chemical Society
|August 17, 2006
Summary
Localized surface plasmon resonance (LSPR) in nanoparticles is sensitive to their environment. This study reveals how molecular resonances influence LSPR, showing wavelength-dependent shifts and line shape changes.
Area of Science:
- * Nanoparticle optics
- * Molecular spectroscopy
- * Plasmonics
Background:
- * Localized surface plasmon resonance (LSPR) peak location in noble metal nanoparticles is sensitive to the surrounding refractive index.
- * Understanding environmental interactions is crucial for plasmonic applications.
Purpose of the Study:
- * To investigate the influence of interacting molecular resonances and nanoparticle resonances on LSPR.
- * To explore new phenomena arising from these interactions.
Main Methods:
- * Analysis of LSPR peak shifts and line shapes induced by resonant molecules.
- * Application of Kramers-Kronig transformation to molecular resonance absorption spectra.
- * Discrete dipole approximation (DDA) calculations for quantitative assessment.
Main Results:
- * LSPR peak shifts and line shapes induced by resonant molecules exhibit wavelength-dependent variations.
- * The oscillatory dependence of the LSPR peak shift correlates with the real part of the refractive index derived from Kramers-Kronig analysis.
- * DDA calculations indicate a necessary scaling of the Kramers-Kronig index to align with experimental observations.
Conclusions:
- * Interactions between molecular and nanoparticle resonances introduce complex, wavelength-dependent effects on LSPR.
- * The Kramers-Kronig relationship provides a framework for understanding these shifts, but requires experimental calibration.
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