Vibrational spectroscopy used in polymorphic analysis

Vibrational spectroscopy includes several techniques, the most important being mid-infrared (MIR), near-IR (NIR) and Raman spectroscopies. Vibrational spectrometry covers a series of well-established analytical methodologies suitable for both qualitative and quantitative purposes. Raman and MIR spectroscopies are complementary techniques and usually both are required to measure the vibrational modes of a molecule completely. In the first part of this review, we focus on theoretical aspects related to vibrational techniques, while, in the second part, we discuss important articles published during the period 2000-14 relating to polymorphic analysis.