Fourier Transform Raman spectrometry

Raman spectra of many pure colorless compounds can easily be measured with an instrument incorporating a visible laser, scanning double monochromator, and PMT. However, when spectroscopists attempted to measure the corresponding spectra of real-world samples with this type of instrument, good spectra were rarely obtained. The root cause of this difficulty was fluorescence by the sample, either because of its intrinsic electronic spectrum or, more likely, because of low levels of fluorescent impurities. Even for nonfluorescent samples, it often took at least 30 minutes to measure a reasonably noise-free Raman spectrum. Thus, with the exception of a few spectroscopists in industrial labs who could obtain their information in no other way, Raman spectrometry was considered to be largely 

Fourier Transform Infrared Spectrometry, Second Edition, by Peter R. Griffiths and James A. de Haseth Copyright 2007 John Wiley Sons, Ine. 

The paper of Hirschfeld and Chase can be considered to herald the emergence of Raman spectroscopy as a tmly important technique for analytical chemists. Within two years, at least five companies [Bio-Rad (now Varian), Bomem, Bruker, Nicolet (now Thermo), and Perkin-Elmer (now PerkinElmer)] had introduced commercial 

FT-Raman spectrometers with performance significantly higher than that shown by Hirschfeld and Chase. Although the basic design of these instruments has not changed dramatically over the ensuing 20 years, improvements in the optical filters and detectors have dramatically improved the signal-to-noise ratio of FT-Raman spectra. These and other components are discussed in the next section. 

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Muik, B., Lendl, B., Molina-Diaz, A., and Ayora-Canada, M.J. Direct, reagent-free determination of free fatty acid content in olive oil and olives by Fourier transform Raman spectrometry. Analytica Chimica... 

CJ Petty. Self-absorption in near-infrared Fourier transform Raman spectrometry. Vibr Spectrosc 2 263-269, 1991. 

A Rau. Basic experiments in thin-layer chromatography-Fourier transform Raman spectrometry. J Raman Spectrosc 24 251-254, 1993. 

C-J de Bakker, PM Fredericks. Determination of petroleum properties by fiber-optic Fourier transform Raman spectrometry and partial least squares analysis. Appl Spectrosc 49 1766-1771, 1995. 

With recent developments in analytical instrumentation these criteria are being increasingly fulfilled by physicochemical spectroscopic approaches, often referred to as whole-organism fingerprinting methods.910 Such methods involve the concurrent measurement of large numbers of spectral characters that together reflect the overall cell composition. Examples of the most popular methods used in the 20th century include pyrolysis mass spectrometry (PyMS),11,12 Fourier transform-infrared spectrometry (FT-IR), and UV resonance Raman spectroscopy.16,17 The PyMS technique... 

The analytical technologies used In metabolomic investigations are nuclear magnetic resonance and mass spectrometry alone or in combination with liquid or gas chromatographic separation of metabolites (243). Other techniques include thin-layer chromatography, Fourier-transform infrared spectrometry, metabolite arrays, and Raman spectroscopy. 

Fourier transform near-infrared spectroscopy had been used to determine traces of hydroxy and carboxy functional groups and water in polyesters. Bowden and co-workers [25] monitored the degradation of PVC using Raman microline focus spectrometry. They demonstrated that PVC decomposition is accompanied by the formation of modal polyene chains containing 11-12 or 13-19 double bonds. Bloor [26] has discussed the Fourier transform Raman spectroscopy of polydiacetylenes. Koenig [27] discusses results obtained by the application of infrared and Raman spectroscopy to polymers. 

FrumarovS B., Nemec P., Frumar M., Oswald J., Vlcek M. Synthesis and optical properties of Ge-Sb-S PrCU system glasses. J. Non-Cryst. Solids 1999 256 2S7 266 Galeener F.L., Leadbetter A.J., Stringfellow M.W. Comparison ofthe neutron, Raman, and infrared vibrational-spectra ofvitreous Si02, Ge02, and BeFa- Phys. Rev. B 1983 27 1052 Griffiths P.R., de Haseth J.A. Fourier Transform Infrared Spectrometry, New York John Wiley Sons, 1986, Chapter 10... 

Pascon, F.M. et al. (2012) Morphological and chemical changes in dentin after using endodontic agents fourier transform Raman spectroscopy, energy-dispersive x-ray fluorescence spectrometry, and scaiming electron microscopy study. / Biomed. Opt, 17 (7), 075008. 

In light of the fact that Fourier transform instrumentation was largely responsible for expanding Raman spectroscopy into the analytical laboratory, it is perhaps interesting to consider why Raman spectroscopy is so popular today but Fourier transform Raman does not play the dominant role. After a discussion of the poor sensitivity of NIR Raman spectrometry using a scanning monochromator with PMT detection in Section 18.1, it was stated To improve this situation, either a multichannel or multiplex measurement was needed and the multiplex measurement came first. Multichannel measurements came very shortly afterward, however, and instruments based on polychromators with silicon-based charge-coupled-device (CCD) array detectors have become more popular than FT-Raman spectrometers. In this section we compare the performance of FT- and CCD-Raman spectrometers. 

Griffiths PR and de Haseth JA (1986) Fourier Transform Infrared Spectrometry. New York John Wiley. Herzberg G (1945) Infrared and Raman Spectra of Polyatomic Molecules. New York Van Nostrand. 

Friedel-Crafts catalysts, 329, 331 Friedel-Crafts reaction, 297, 361 Front-end reactions, 235 FT Raman spectroscopy, 387 FTIR spectrometry. See Fourier transform infrared (FTIR) spectrometry Fuel cells, 272-273 Full prepolymers, 236, 237 Functionalized polyolefins, 459-460... 

Spectroscopy, 490. See also 13C NMR spectroscopy FT Raman spectroscopy Fourier transform infrared (FTIR) spectrometry H NMR spectroscopy Infrared (IR) spectroscopy Nuclear magnetic resonance (NMR) spectroscopy Positron annihilation lifetime spectroscopy (PALS) Positron annihilation spectroscopy (PAS) Raman spectroscopy Small-angle x-ray spectroscopy (SAXS) Ultraviolet spectroscopy Wide-angle x-ray spectroscopy (WAXS)... 

Altered surfaces have been inferred from solution chemistry measurements (e.g., Chou and Wollast, 1984, 1985) and from spectroscopic measurements of altered surfaces, using such techniques as secondary ion mass spectrometry (for altered layers that are several tens of nm thick (e.g., Schweda et al, 1997), Auger electron spectroscopy (layers <10 nm thick (e.g., Hochella, 1988), XPS (layers <10 nm thick (e.g., Hochella, 1988 Muir et al, 1990), transmission electron microscopy (TEM, e.g., Casey et al, 1989b), Raman spectroscopy (e.g.. Gout et al, 1997), Fourier transform infrared spectroscopy (e.g., Hamilton et al, 2001), in situ high-resolution X-ray reflectivity (Farquhar et al, 1999b Fenter et al, 2003), nuclear magnetic resonance (Tsomaia et al, 2003), and other spectroscopies (e.g., Hellmann et al, 1997). 

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