The Evolution of Vibrational Spectroscopies

The fundamentals of transmission/absorption IR spectroscopy were developed in the last decades of the nineteenth century and in the very first years of the twentieth century [1], and, as a consequence, IR spectroscopy rapidly became one of the most widely used techniques for chemical analysis. 

Subsequently, it has been recognized that other IR techniques (reflection, emission and photothermal techniques) can also be applied, and that IR spectroscopy only gives partial information on the vibrational structure of most polyatomic species. In fact, selection rules apply to IR light absorption phenomena, so that only vibrational modes that are associated with changes of the molecular dipolar moment can be directly excited. 

Alternatively the entire, or part of the, vibrational spectra of polyatomic chemical species can be obtained by looking at the inelastic scattering of particles other than 

Metal Oxide Catalysis. Edited by S. David Jackson and Justin S. J. Hargreaves Copyright 2009 WILEY-VCH Verlag GmbH Co. KGaA, Weinheim ISBN 978-3-527-31815-5 

Application of IR Spectroscopy to the Surface Chemistry of Oxide-Based Materials a Historical Perspective 

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