THz frequency dynamics of network/guest atom systems: Liquid water, clathrates, and network glasses

Network/guest atom systems show peculiar dynamic behaviors at THz frequency region such as the plateau of thermal conductivities and the broad band spectra called the Boson peak. These are commonly realized in network/guest atom systems such as glasses, clathrates and even for liquid water. Though the phenomena are universal, there is no consistent view to explain these on the same basis. This paper, pointing out similar behaviors for these different systems, tries to present a unified view for these peculiar dynamics.