Structural study of Li2S-GeS2 glasses: Ge-S network and local environment of Li

The static structures of (Li2S)(x)(GeS2)(100-x) glasses (x = 0, 20, 30, 40 and 50) were investigated by using a com-bination of diffraction measurements and simulation techniques. The X-ray diffraction results show that the host Ge-S network is formed by linkages of GeS4 tetrahedra. The three-dimensional structure models of Ge-S network were generated by using the X-ray diffraction data and reverse Monte Carlo (RMC) simulation. The RMC models show that the number of edge-sharing GeS4 tetrahedra decreases as Li2S content but its ratio to the number of connections between GeS4 tetrahedra remains substantially constant irrespective of the composition. The Li ion sites in the Ge-S network structures were determined by molecular dynamics (MD) simulation with reference to the previously reported neutron diffraction data. The MD results show that each Li ion is located in a deformed octahedral site consisting of bridging and non-bridging sulphur atoms.