Chemical Molecular Mechanism of SERS

The chemical (or molecular) mechanism reflects increased molecular polarizability tensor ttmoiecuie and consequently Raman cross-section. This mechanism has a number of requirements, such as the existence of special active sites , the formation of a metal-adsorbate chemical bond sometimes referred to as a first-layer effect (Otto 2005). One common model to explain this mechanism is the 

3 Basics of Surface-Enhanced Raman Scattering (SERS) 

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