Reactions between AgI and Rb2AgI3 were studied. Following the formation of product phases, local thermodynamic equilibrium was established, and further reaction occurred via the cation interdiffusion of Ag+ and Rb+. The reaction rate was controlled by the Rb+ diffusion coefficient. By analyzing the reaction kinetics, the diffusion coefficients were calculated for temperatures of 120 to 190C. The coefficient of Ag diffusion was determined by using conductivity measurements. The results could be described by:

D (m2/s) = 4 x 10-6 exp[-67(kJ/mol)/RT]

Solid State Reactions and Transport Properties in the Quasibinary System AgI/RbI. B.Schröder, V.Leute: Journal of Physics and Chemistry of Solids, 1980, 41[8], 827-35