On the influence of water on THz vibrational spectral features of molecular crystals

The collective vibrations in molecular crystals can be probed using terahertz spectroscopy, providing unique characteristic spectral fingerprints. However, the association of the spectral features to the crystal conformation, crystal phase and its environment is a difficult task. We present a combined computational-experimental study on the incorporation of water in lactose molecular crystals, and show how simulations can be used to associate spectral features in the THz region to crystal conformations and phases. Furthermore, we also show that water does not play only a perturbative role but fully participates in the emergence of the THz vibrations