A vibrational study of inulin by means of experimental and theoretical methods

Inulin, a natural polymer formed by several units of fructose and just one unit of glucose, is found in different plants or directly in some fruits or vegetables. Due to its structure it has been used in many applications from medicine, pharmacology or food industry. In spite of this, a complete vibrational analysis of the molecule is missing in the literature. Moreover, there are contradictory results regarding the assignment of certain vibrational modes. Therefore, the aim of this study was to obtain a comprehensive vibrational investigation of inulin by means of experimental (FT-IR and Raman spectroscopy) and theoretical (density functional theory -DFT simulations) methods.