Transport coefficients in superionic α-AgI
Tóm tắt
A phenomenological theory is given for the time dependence of the relaxation process of an α-AgI sample which has been previously polarized by the application of a voltage. The electromotive force caused by the internal electric field due to the polarized charge distribution is given by a series of exponential terms as a function of Dt, with D being the effective diffusion constant and t the time. The diffusion constants are obtained at several temperatures. In addition, the AC conductivity was measured for the same specimen. The results are analyzed with the help of a generalized Drude theory. Using both the results of the diffusion constant D and the AC conductivity, deviations from the Nernst-Einstein's relation are derived. Furthermore, computer simulations on these quantities were carried out by using well-established pairwise potentials. The agreement is satisfactory.
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