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[...]... SIMPLE RAMAN SPECTRUM: RAMAN SPECTRUM OF WATER Let us explore a Raman spectrum of water as an example of simple Raman spectrum Figure 1.3 shows the Raman spectrum of water measured using excitation light (Arþ FIGURE 1.2 Stokes and anti-Stokes Raman scattering INTRODUCTION TO RAMANSPECTROSCOPY 5 laser) with a frequency of 488.0 nm The abscissa indicates three different ways of expressing the frequency of. .. Wiley & Sons, Inc 1 2 PHARMACEUTICAL APPLICATIONS OF RAMAN SPECTROSCOPYRaman and Krishnan [Raman 1928] discovered the scattering effect that is named after Raman and that earned him a Nobel Prize in 1930 Raman spectroscopy, however, developed relatively slowly for several reasons First, Raman experiments were not easy to carry out because of the extremely weak intensity of the Raman scattered light... reflect changes in the surroundings of the molecules and are thus helpful in studying intra- and intermolecular interactions 1.1 HISTORY OFRAMANSPECTROSCOPYRamanspectroscopy is based on the effect of radiation being scattered with a change of frequency and its history goes 80 years back It was in 1928 that Indian scientists ˇ ˇ´ Pharmaceutical Applications of Raman Spectroscopy, Edited by Slobodan... to Ramanspectroscopy as a means of online or outdoor analysis 5 A valuable application ofRamanspectroscopy in fundamental research is for examination of ultrahigh speed phenomena A combination of a pulse laser and a multichannel detector allows acquisition of time-resolved spectra even in the order of femtoseconds Ramanspectroscopy is, therefore, frequently used to study the excited states of molecules... ‘‘The Handbook of Vibrational Spectroscopy, ’’ by P Griffiths and J Chalmers, and ‘‘Analytical Applications of Raman Spectroscopy by M Pelletier However, the literature on Raman theory is far more diverse, with the excellent monograph by R McCreery standing out as the text that most comprehensively covers all the elements ofRamanspectroscopy as a technique From the perspective of the pharmaceutical. .. that we can easily study molecules in aqueous solutions, which is very important for applicability ofRamanspectroscopy 1.4 CHARACTERISTICS OFRAMANSPECTROSCOPYRamanspectroscopy is characterized by the following features: 1 Ramanspectroscopy permits acquisition of the spectra in situ Monitoring of a reaction in a flask online, for example, can simply be accomplished by irradiating laser light directly... number of contributions that touch on the use ofRamanspectroscopy in various parts of the business, but there is no single volume that collects and lists those efforts The book in your hands is an attempt to gather and order the pharmaceutical applications of Raman in a single tome Regarding the pharmaceutical industry, near-infrared (NIR) spectroscopy is unquestionably the spectroscopic method of choice,... the structures of reaction intermediates Ramanspectroscopy is complementary to and often compared with IR spectroscopy in various aspects Comparison with NIR spectroscopy is also INTRODUCTION TO RAMANSPECTROSCOPY 7 appropriate with regard to industrial applications and it will be mentioned below These are the principal points of comparison between the Raman and IR methods: 1 Measurement of spectra from... selective examination of parts of the molecule For instance, in an enzyme molecule with the molecular weight of tens of thousands one can selectively acquire Raman signal from an active site of that enzyme that has the molecular weight of only a few hundreds To the contrary, IR spectroscopy only allows for acquisition of average spectra of the sample 1.5 THE CLASSIC THEORY OFRAMAN EFFECT The classic... It thus follows that the mode I is Raman- active With respect to the normal mode vibrations II, IIIa, and IIIb (all of which are IR-active), the values a at the both ends of the vibrations 10 PHARMACEUTICAL APPLICATIONS OF RAMAN SPECTROSCOPY FIGURE 1.5 Changes of the polarizability ellipsoid for the vibrations of CO2 molecule The n1 vibration is Raman active because of the change in the polarizability . INC., PUBLICATION
PHARMACEUTICAL
APPLICATIONS OF
RAMAN SPECTROSCOPY