Applications of FT-Raman Spectrometry

Recently, a number of portable Raman spectrometers have been introduced for held measurements of drugs, explosives, and other hazardous materials. These instruments are usually equipped with inexpensive CCD cameras that operate at room temperature. The sensitivity of uncooled CCD arrays is over an order of magnitude less than that of detector arrays that have been thermoelectrically cooled to -40 or -70°C, so that the sensitivity of these instruments may actually be less than that of an FT-Raman spectrometer. 

Another important advantage of FT-Raman spectrometers is their wavenumber stability (called the Cannes advantage). This property of FT-Raman spectrometers is particularly important for process measurements where regular cahbration may not be possible. Although the manufacturers of dispersive Raman spectrometers claim to have overcome the problem by incorporating neon lamps, variations in the wavelength scale are still evident when the temperature of the monochromator varies. 

Good FT-Raman spectra can usually be measured in 5 or 10 min from almost any type of sample. Thus, if data acquisition time is not the limiting factor for a Raman measurement and a choice is to be made regarding purchase of a Raman spectrometer, the purchase of an FT-Raman instmment should be given serious consideration. 

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In Chapters 2 to 8 we describe the theory and instrumentation needed for an appreciation of the way that Fourier transform infrared and Raman spectra are measured today. The sampling techniques for and applications of FT-Raman spectrometry are described in Chapter 18. The remaining chapters cover the techniques and applications of absorption, reflection, emission, and photoacoustic spectrometry in the mid- and near-infrared spectral regions. 

APPLICATIONS OF FT-RAMAN SPECTROMETRY 18.4.1. Standard Raman Spectroscopy... 

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