Methods for Describing the Electromagnetic Properties of Silver and Gold Nanoparticles

Department of Chemistry, Northwestern University, Evanston, Illinois 60208-3113.
Accounts of Chemical Research (Impact Factor: 22.32). 09/2008; 41(12):1710-20. DOI: 10.1021/ar800028j
Source: PubMed


This Account provides an overview of the methods that are currently being used to study the electromagnetics of silver and gold nanoparticles, with an emphasis on the determination of extinction and surface-enhanced Raman scattering (SERS) spectra. These methods have proven to be immensely useful in recent years for interpreting a wide range of nanoscience experiments and providing the capability to describe optical properties of particles up to several hundred nanometers in dimension, including arbitrary particle structures and complex dielectric environments (adsorbed layers of molecules, nearby metal films, and other particles). While some of the methods date back to Mie’s celebrated work a century ago, others are still at the forefront of algorithm development in computational electromagnetics.

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    • "Plasmonic nanostructures of noble metals such as silver and gold exhibit a phenomenon known as surface-enhanced Raman scattering (SERS) which is based on the strong amplification of the scattering cross-section of molecules absorbed thereon [1] [2]. There are two mechanisms to such an enormous enhancement of SERS: electromagnetic enhancement that is associated with the localized surface plasmon resonances occurring at the surfaces of roughened metal substrates or metal clusters and chemical enhancement which is associated with the direct charge transfer or indirect electron–hole pair excitation processes [3] [4]. In the pastdecades, research on SERS which is recognized as one of the most modern laser spectroscopic techniques holds great promise for the fields of analytical chemistry, forensics, food safety, threat detection , and medical diagnostics and the reported detection limit has reached the single molecule level due to its high level detection sensitivity and specificity. "
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