The dielectric properties especially of glassy materials are nowadays explored at widely varying temperatures and pressures without any gap in the spectral range from Hz up to the Infrared, thus covering typically 20 decades or more. This extraordinary span enables to trace the scaling and the mutual interactions of relaxation processes in detail, e. g. the dynamic glass transition and secondary relaxations, but as well far infrared vibrations, like the Boson peak. Additionally the evolution of intra-molecular interactions in the course of the dynamic glass transition is also well explored by ( The Scaling of Relaxation Processes - Friedrich Kremer, Alois Loidl od authora Friedrich Kremer, Alois Loidl a nakladatelství za skvělé ceny na e-shopu Martinus. cz.