Surface-enhanced Raman matrix

Thus far, we have reviewed basic theories and experimental techniques of Raman spectroscopy. In this chapter we shall discuss the principles, experimental design and typical applications of Raman spectroscopy that require special treatments. These include high pressure Raman spectroscopy, Raman microscopy, surface-enhanced Raman spectroscopy, Raman spectroelectro-chemistry, time-resolved Raman spectroscopy, matrix-isolation Raman spectroscopy, two-dimensional correlation Raman spectroscopy, Raman imaging spectrometry and non-linear Raman spectroscopy. The applications of Raman spectroscopy discussed in this chapter are brief in nature and are shown to illustrate the various techniques. Later chapters are devoted to a more extensive discussion of Raman applications to indicate the breadth and usefulness of the Raman technique. 

Surface-Enhanced Raman Spectroscopy (SERS) Raman Spectroelectrochemistry Time-Resolved Raman (TR-) Spectroscopy Matrix-Isolation Raman Spectroscopy 2D Correlation Raman Spectroscopy Raman Imaging Spectrometry Nonlinear Raman Spectroscopy References... 

See also Matrix Isolation Studies By IR and Raman Spectroscopies Nonlinear Optical Properties Nonlinear Raman Spectroscopy, Instruments Nonlinear Raman Spectroscopy, Theory Photoacoustic Spectroscopy, Theory Raman Optical Activity, Applications Raman Optical Activity, Theory Rayleigh Scattering and Raman Spectroscopy, Theory Surface-Enhanced Raman Scattering (SERS), Applications. 

For trace analysis in fluids, some Raman sensors (try to) make use of the SERS effect to increase their sensitivity. While the basic sensor layout for SERS sensors is similar to non-enhanced Raman sensors, somehow the metal particles have to be added. Other than in the laboratory, where the necessary metal particles can be added as colloidal solution to the sample, for sensor applications the particles must be suitably immobilised. In most cases, this is achieved by depositing the metal particles onto the surfaces of the excitation waveguide or the interface window and covering them with a suitable protection layer. The additional layer is required as otherwise washout effects or chemical reactions between e.g. sulphur-compounds and the particles reduce the enhancement effect. Alternatively, it is also possible to disperse the metal particles in the layer material before coating and apply them in one step with the coating. Suitable protection or matrix materials for SERS substrates could be e.g. sol-gel layers or polymer coatings. In either... 

Surface-enhanced resonance Raman scattering causes fluorescence quenching. It is very often possible to identify SERRS spectrum from a dye in a matrix where resonance Raman scattering is completely obscured by the fluorescence. 

A recent SPP-resonance Raman experiment explored the structural conformations of several carbon clusters. The Ci6, Ci8, and C20 clusters were created by laser ablation of a graphite rod and then deposited into a N2 matrix on the silvered SPP prism surface. After finding the SPP resonance condition (as described in Section VLB), Raman spectra were collected with six different excitation wavelengths. SPP-Raman enhancement is operative in all six spectra. The strong dependence of the Raman spectra for the C20 cluster on Xex shown in Fig. 10 indicates that enhancement due to RRS is simultaneously operative. It is important to emphasize that these signals shown in this figure are obtained from ca. 10 clusters in the laser focal spot. Upon comparing the Raman peak frequencies for all three carbon clusters to theoretical predictions, the researchers were able to hypothesize that all three carbon clusters adopt either a linear chain or poly-... 

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