Introduction to IR Spectrometry

IR spectrometry differs from UV-VIS spectrophotometry in the following ways  

Absorption of IR light results in vibrational energy transitions rather than electronic transitions. The concept of vibrational energy transitions was introduced in Chapter 7. 

While liquid solutions are often analyzed in IR work, pure liquids and undissolved solids, including polymer films, are also often analyzed, as are gases. 

In IR work, the containers that hold liquids or liquid solutions in the path of the light are not called cuvettes. They are called liquid sampling cells. 

IR spectra are usually transmission spectra rather than absorption spectra, and wavenumber, rather than wavelength, is plotted on the x-axis. 

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