Concentration Effects of Silver Ions on Forming Cooperative Conduction Path in Superionic Melts

Abstract

In Ag-based superionic melts, medium-range order in the Ag-Ag partial correlation relating to the fast ionic conducting path of Ag ions was analyzed as a function of Ag concentration. High energy x-ray diffraction measurements for molten Ag 2 Se and (Ag 2 Se) x (AgI) 1-x mixtures and (RbI) y (AgI) 1-y were carried out. In molten (Ag 2 Se) x (AgI) 1-x mixtures, a first sharp diffraction peak (FSDP) is not observed in the total structure factor for x = 0.2 and 0.3. On the other hand, molten (RbI) y (AgI) 1-y mixture have a FSDP at small Q region than that of molten AgI. It may suggest that the correlation length of the fluctuation of Ag distribution varies with Ag concentration. In the reverse Monte Carlo analysis for molten Ag 2 Se, it is confirmed that the FSDP of Ag-Ag partial structure factor shifts to short length side compared with molten AgI.

Concentration Effects of Silver Ions on Ionic Conductivities of Molten Silver Halides

“…Structural investigation of molten (RbCl) c (AgCl) 1-c and (RbI) c (AgI) 1-c mixtures, especially reduction of Ag-Ag partial correlations is indispensable to complete full discussion on transport properties in relation with unusual flat Ag-Ag pdf of molten AgCl and anomalous Ag migration in molten AgI. We have already measured the structure of molten (RbI) c (AgI) 1-c mixtures [28] and we plan to measure the structure of molten (RbCl) c (AgCl) 1-c mixtures. We will discuss the relation between transport properties and the partial structures in a near future.…”

“…The (RbI) c (AgI) 1-c mixtures has stoichiometric compound RbAg 4 I 5 which shows the superionic phase even at room temperature [23][24][25][26][27], and its structure factor at molten phase has the largest scale of medium-range order in the molten (RbI) c (AgI) 1-c system [28]. We have two motivations in this study.…”

Local Structure of Superionic Glass Agx(GeSe3)1-x,x=0.565

“…It was revealed that the Ag distribution in Ag 0,5 (GeSe 3 ) 0.5 has a tendency of forming chain-like fragments even in the molten state, which is characteristic feature in the Ag based superionic melts such as AgI [4] and Ag 2 Se [5]. The grown-up of medium-range order with decreasing temperature is related to the process of Ag ionic conduction path formation in the molten and supercooled liquid states [3].…”

Phases Transition in Carbon-doped Silver Iodide

“…Figure 2 shows the behavior conductivity and its abrupt jump in conductivity using Equation (7) and the probability distribution function (5). The fits are good because the carriers follow a temperature-dependent probability distribution.…”

“…Superionic conductors allow the movement of ions through their structure, showing unusually high ionic conductivity values (similar to liquid electrolytes). Silver iodide or AgI, since its high conductivity was discovery in 1914 [1] has been extensively studied from both experimentally [2][3][4][5][6] and theoretically [7][8][9][10][11][12][13] points of view. At atmospheric pressure, AgI is polymorphic [14] with phases denoted by γ, β, and α, accessible with increasing temperature T. At room temperature, the γ phase [15] is thermodynamically meta-stable with a zinc blende structure and the β phase [16] is stable with a wurtzite structure.…”