Application in Raman

Altkom R, Koev I, Van Duyne RP, Litoija M (1997) Low-loss liquid-core optical fiber for low-refractive index liquids fabrication, characterization, and application in Raman spectroscopy. Appl Opt 36 8992-8998... 

Only a few works have been performed on pattern recognition applications in Raman spectroscopy. This is probably due to the lack of suitable computer-readable spectra. Methods of coding and classification would be the same as used for infrared spectra. 

Polymer applications in Raman spectroscopy were reviewed [375,407,408], as well as general applications in the chemical industry [52,384,409]. For Raman spectroscopy of synthetic polymers, cfr. ref. [394], The use of Raman spectroscopy in art analysis has recently been reviewed [410,410a]. For applications of non-classical Raman spectroscopy, cfr. ref. [411] and for FT-Raman spectroscopy, cfr. also ref. [412]. A textbook is available [394]. 

Figure Bl.2.11. Biologically active centre in myoglobin or one of the subunits of haemoglobin. The bound CO molecule as well as the proximal and distal histidines are shown m addition to the protohaeme unit. From Rousseau D L and Friedman J M 1988 Biological Applications of Raman Spectroscopy vol 3, ed T G Spiro (New York Wiley). Reprinted by pennission of John Wiley and Sons Inc.

There are tluee very important sources of up-to-date infonnation on all aspects of Raman spectroscopy. Although papers dealing with Raman spectroscopy have appeared and will continue to appear in nearly every major chemical physics-physical chemistry based serial. The Journal of Raman Spectroscopy [35] is solely devoted to all aspects, both theoretical and experimental, of Raman spectroscopy. It originated in 1973 and continues to be a constant source of mfonuation on modem applications of Raman spectroscopy. 

To emphasize the versatility of Raman spectroscopy we discuss just a few selected applications of Raman based spectroscopy to problems in chemical physics and physical chemistry. 

In addition to the many applications of SERS, Raman spectroscopy is, in general, a usefiil analytical tool having many applications in surface science. One interesting example is that of carbon surfaces which do not support SERS. Raman spectroscopy of carbon surfaces provides insight into two important aspects. First, Raman spectral features correlate with the electrochemical reactivity of carbon surfaces this allows one to study surface oxidation [155]. Second, Raman spectroscopy can probe species at carbon surfaces which may account for the highly variable behaviour of carbon materials [155]. Another application to surfaces is the use... 

Clearly the broad survey of current activity in Raman spectroscopy revealed by this simple snapshot promises an exciting flitiire tiiat is likely to find surprising new applications, even as present methods and applications become refined. 

Shim M G and Wilson B C 1997 Development of an in vivo Raman spectroscopic system for diagnostic applications J. Raman Spectrosc. 28 131-42... 

D. A. Long. Raman Spectroscopy. McGraw-Hill, New York, 1977. A standard reference work on Raman spectroscopy with much theoretical detail on the underlying physics. Most of the needed equations for any application of Raman spectroscopy can be found in this book. 

Recent developments in Raman equipment has led to a considerable increase in sensitivity. This has enabled the monitoring of reactions of organic monolayers on glassy carbon [4.292] and diamond surfaces and analysis of the structure of Lang-muir-Blodgett monolayers without any enhancement effects. Although this unenhanced surface-Raman spectroscopy is expected to be applicable to a variety of technically or scientifically important surfaces and interfaces, it nevertheless requires careful optimization of the apparatus, data treatment, and sample preparation. 

Until today the only available data obtained by direct sampling of a prototype battery system concerning mass flow of the complexing agents as well as the Br2 produced in both the aqueous and non-aqueous electrolyte phases have been gained by application of Raman spectroscopy [89, 90]. 

The resonance Raman effect — review of the theory and of applications in inorganic chemistry. R. J. H. Clark and B. Stewart, Struct. Bonding (Berlin), 1979, 36, 1-80 (110). 

Here, selected, more established laser diagnostic techniques will only be briefly named with their principal area of application in combustion measurements, but not further described details on these and other methods can be found in the above-mentioned literature and references cited therein. Workhorse techniques in combustion diagnostics include Raman and Rayleigh... 

Decades of combined spectral and chemistry expertise have led to vast collections of searchable user databases containing over 300 000 UV, IR, Raman and NMR spectra, covering pure compounds, a broad range of commercial products and special libraries for applications in polymer chemistry (cf. Section 1.4.3). Spectral libraries are now on the hard disks of computers. Interpretation of spectra is frequently made only by computer-aided search for the nearest match in a digitised library. The spectroscopic literature has been used to establish computer-driven assignment programs (artificial intelligence). 

Applications Sollinger and Sawatzki [793] have reported the use of TLC-Raman for routine applications, e.g. TLC of hydroxybenzenes (including hydro-quinone and pyrogallol) on conventional, silica gel and specific Raman-TLC plates (coated with spherical silica gel). Databases were used for identification of substances. Typical detection limits were in the low p,g region per application, Micro-Raman spectrometry has been employed in analysing TLC fractions from polymer additives within a detection limit... 

Various techniques have been introduced which still lack specific applications in polymer/additive analysis, but which may reasonably be expected to lead to significant contributions in the future. Examples are LC-QToFMS, LC-multi-API-MS, GC-ToFMS, Raman spectroscopy (to a minor extent), etc. Expectations for DIP-ToFMS [132], PTV-GC-ToFMS [133] and ASE are high. The advantages of SFC [134,135], on-line multidimensional chromatographic techniques [136,137] and laser-based methods for polymer/additive analysis appear to be more distant. Table 10.33 lists some innovative polymer/additive analysis protocols. As in all endeavours, the introduction of new technology needs a champion. 

Transition metal oxides, rare earth oxides and various metal complexes deposited on their surface are typical phases of DeNO catalysts that lead to redox properties. For each of these phases, complementary tools exist for a proper characterization of the metal coordination number, oxidation state or nuclearity. Among all the techniques such as EPR [80], UV-vis [81] and IR, Raman, transmission electron microscopy (TEM), X-ray absorption spectroscopy (XAS) and NMR, recently reviewed [82] for their application in the study of supported molecular metal complexes, Raman and IR spectroscopies are the only ones we will focus on. The major advantages offered by these spectroscopic techniques are that (1) they can detect XRD inactive amorphous surface metal oxide phases as well as crystalline nanophases and (2) they are able to collect information under various environmental conditions [83], We will describe their contributions to the study of both the support (oxide) and the deposited phase (metal complex). 

Guo, L., Huang, Q., Li, X. and Yang, S. (2001) Iron nanoparticles synthesis and applications in surface enhanced Raman scattering and electrocatalysis. Physical Chemistry Chemical Physics, 3, 1661-1665. 

N.J. Everall, Industrial applications of Raman spectroscopy. In D.L. Andrews and A.A. Demidov (Eds.), An Introduction to Laser Spectroscopy, Plenum Press, New York, 1995, pp. 115-131. 

N. Everall, Chapter 4, Raman spectroscopy of synthetic polymers. In M.J. Pelletier (Ed.), Analytical Applications of Raman Spectroscopy, Blackwell Science, Oxford, 1999, pp. 127-192. 

One possibility of circumventing the problem of the solvent absorption is to use Raman spectroscopy, where the probing light is in the visible, and this approach is detailed in section 2.1.7. However, the difficulties experienced with the application of Raman to the electrode/electrolyte interface (vide infra), refocused attention on the seductive simplicity of IR spectroscopy, particularly as the technique had proved invaluable in the study of species at the gas/solid and vacuum/solid interfaces. 

Nabiev, I., Chourpa, I., and Manfait, M. (1994) Applications of Raman and surface-enhanced Raman-scattering spectroscopy in medicine, J. Raman Spectrosc. 25, 13-23. 

The following examples, from the literature and our own work, demonstrate some of the potential applications for Raman spectroscopy in the pharmaceutical sciences. 

Clearly, the potential applications for vibrational spectroscopy techniques in the pharmaceutical sciences are broad, particularly with the advent of Fourier transform instrumentation at competitive prices. Numerous sampling accessories are currently available for IR and Raman analysis of virtually any type of sample. In addition, new sampling devices are rapidly being developed for at-line and on-line applications. In conjunction with the numerous other physical analytical techniques presented within this volume, the physical characterization of a pharmaceutical solid is not complete without vibrational analysis. 

Yan B, Gremlich HU, Moss S, Coppola GM, Sun Q, Liu LJ (1999) Comparison of various FTIR and FT Raman methods applications in the reaction optimisation stage of combinatorial chemistry. J Comb Chem 1 46-54... 

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