Experimental and theoretical THz spectroscopy of solid saccharides

Terahertz time-domain spectroscopy (THz-TDS) is a powerful tool for probing collective molecular vibrational modes of biomolecules. In this study, we used THz-TDS to investigate the low-energy vibrational modes of a group of organic molecules belonging to saccharides (or carbohydrate) in their solid state. Ab-initio simulations based on density functional theory (DFT) were carried out by employing a state-of-the-art method for the calculation of the weak intermolecular forces driving the collective motion of organic molecules. This approach allowed us to identify and analyze the low-energy vibrations finding their percentage contributions of intermolecular and intramolecular motion of the optical phonons.