Structural and transport influence of dissolving AgBr into AgI in super ionic and molten phases by molecular dynamics simulations

Structural influence by dissolving AgBr into AgI, i.e., Ag(BrxI1-x) (x < 0.5) system in superionic and molten phases are investigated by molecular dynamics (MD) simulations using the Parrinello-Rahman-Vashishta (RVP) type potentials. The partial pair distribution functions and bond angle distributions obtained by MD indicate that the superionic phase is reproduced for the concentration range, Ag(BrxI1-x) (x < 0.5), at the corresponding temperature. The descriptions of the pair distribution functions obtained by MD in molten phases are in good agreement with the neutron diffraction experiments. The partial pair distribution functions suggest that the ion distributions around I and Br ions have different features in both super ionic and molten phases. Dissolving AgBr into superionic AgI yields Ag distribution change on (1,0,0) plane as increasing Br ions at the lattice points. The transport coefficients are also obtained in these two phases by MD. The obtained partial conductivities in molten phase are in good agreement with experiments and the ratios of partial conductivities at constant concentration are found being constant regardless of its temperature.