THE STRUCTURE CHARACTERIZATION OF A SUPER IONIC-CONDUCTING GLASS CuI-Cu₂MoO₄ BY PULSED NEUTRON SCATTERING. Kenji Suzuki, Kaoru Shibata and Takao Tsurui, Institute for Metals Research, Tohoku University, Sendai 980, Japan

A composite glass CuI-Cu₂MoO₄ has been known to have a very high ionic conductivity at room temperature corresponding to ionic liquids. Based on the observation of pulsed neutron scattering from the glass, we have found that the skeleton structure of the glass is constructed from a mutual connection of MoO₄ tetrahedron and MoO₆ octahedron. Nano-clusters of CuI are uniformly dispersed in the glass matrix. The atomic vibrational mode between Cu and I in the glass at room temperature is rather close to that of (-CuI crystalline state near the melting point. The fast ionic conduction by the CuI-Cu₂MoO₄ glass is directly demonstrated to arise from the long-range translational diffusion of Cu⁺ ions, by measuring the high resolution quasielastic neutron scattering in the energy range below 100 (eV. In addition to the Boson peak, a significantly excess intensity is found in the inelastic neutron scattering in the energy range below 3 meV at the temperature above 200 K. The correlation between the static and dynamic structure of the glass will be discussed.