Electrcal Properties of liquids and glasses composed of chemically different substances

点击翻译按钮获取中文摘要

The results of the present project are summarized as follows :1.Metal-nonmetal systems : We have studied the electric conductivity and Cs-133 NMR in the Cs-ammonia-methylamine system and correlated the observed concentration flucutuation and the metal-nonmetal (MNM) transition of the system. Low field EPR measuremts at 200 MHz were carried out for the Na-ammonia system to show the local metallization prior to the bulk MNM transition. Precipitation of Ag and Bi nano-particles in borate glasses was investigated and the size dependence has been found for their physical properties such as plasmon absorption or melting temperature. The NM transition in the Tl-Ge-Te system has been correlated to the thermodynamic properties obtained from EMF measuremnts.2.Organic-inorganic mixed superionic conductors : The electrical conductivity of AgI-tetraalkylammonium iodide mixed glasses has been studied as a function of volume fraction of AgI,which shows a percolation transition from the superionic to insulator states. Microscopic investigations were also made with NMR,EXAFS,neutron and X-ray small angle scattering.3.Ionic salt-molecular liquid systems : The viscosity of the LiNO_3-glycerol system increases with salt concentration, while the electrical conductivity decreases. Similar measurements have been made for the LiCl-water system. Network structures composed of solvated lithium ions and solventmolecules have been suggtested.From these results it is concluded that in liquids and glasses composed of chemically different substances the local in homogeneities due to phase separation or complex formation determine electrical properities of the bulk systems.