Various applications of resonance Raman spectroscopy

One of the most useful advantages of resonance Raman spectroscopy is its ability to record spectra at very low concentrations. For example, Thibeau et al. (1978) have shown that this type of spectroscopy is able to detect hazardous chemicals in water. Nitrophenol-based pesticides or fungicides could be detected at concentrations below Ippm. 

The use of resonance Raman spectroscopy for the study of transient species, including free radicals, has been reviewed be Hester (1978). Provided only that excitation may be achieved within an intense absorption band specific to the intermediate species, selective resonance enhancement permits the detection and characterization of such species at concentrations in the lO - 10 molar range without serious interference from spectra of other dissolved species such as excess reactant and product molecules. 

A further area which had attracted an increasing amount of attention is that of the resonance Raman spectra of structurally simple inorganic molecules, particularly those possessing allowed electronic transitions in the visible region. Clark (1975) and Clark and Dines (1986) have reviewed the application of resonance Raman excitation in inorganic chemistry. 

Also linear chain complexes such as Pt(etn)4Cl3 which is known colloquially as Wolf-fram s red (etn being an abbreviation for ethylamine) have been studied successfully by resonance Raman spectroscopy (Clark, 1984). As example, we show in Fig. 6.1-12 the resonance Raman spectrum of a related halogen-bridged linear-chain species, [Pt(pn)2] [Pt(pn)2Br2] [Cu3Br5]2 (Clark et al., 1980). Although this species contains a complicated copper bromine chain, the resonance Raman spectrum (Fig. 6.1-12) is completely dominated by bands attributed to the v fundamental and its overtones n U[ of the platinum-bromine chain. 

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