Which are the principles and application of IR spectroscopy

IR spectroscopy is a technique that can be employed for both quantitative and qualitative analysis. It is based upon the interaction between electromagnetic waves and compounds. However while the UV waves carry enough energy to induce the ionization of a molecule the IR waves carry the energy necessary for a chemical bound to vibrate. In an IR spectra a chemical bound won't however vibrate if it is perfect symmetrical. The energy necessary for a bound to vibrate depends on the strength of a bound or on the size of the element involved in the chemical bound.