Types of Raman Spectroscope

For specific types of data, needed developments are incorporated in the Raman spectroscopie analysis. These are  

Enhances the Raman scattering by adsorbing molecules on rough metal surfaces (colloidal metals, e.g. gold/silver) and the enhancement factor may be of the order of IQii. 

To enhance the vibrational modes of the excited electronic states of a molecule or crystal, the excitation wavelength is matched accordingly. This is useful for studying large molecules. 

In this method, Raman signals are enhanced using a metallic tip (usually silver or gold coated) in the vicinity of the molecules of interest. The spatial resolution is of the size of the tip (20-30 mn). This is a very useful method for bio analysis. 

It studies the polarization of Raman scattered light using a polarized laser excitation and a polarization analyzer. The molecular orientation and vibrational symmetry information (relating to the molecular shape e.g. polymorph analysis, liqnid crystal study etc.) can be obtained by this techniqne. 

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