Sequential hypersonic dampings due to fast ion diffusion and structural relaxation in (AgI)x(AgPO3)1−x ionic liquids

doi:10.1016/0167-2738(86)90101-3

Solid State Ionics

Volumes 18–19, Part 1, January 1986, Pages 141-146

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Abstract

We report the novel observations that in the liquid states of fast ion conducting glasses two independent relaxation processes can be distinguished by Brillouin scattering. Spectra of the (AgI)_x(AgPO₃)_1−x systems have been studied between x=0 and 0.5 and above 0.4 reveal two independent hypersonic phonon damping mechanisms attributed to structural relaxation and to Ag⁺ diffusion. With increasing AgI content, the absorption due to mobile Ag⁺ shifts to lower temperatures in accordance with conductivity relaxation time data. The results imply that we have observed for the first time the liquid state equivalent of the mobile cation internal friction peak well known from the lower frequency mechanical studies on other ion conducting glasses. The relaxation strength of the fast ion diffusion mode is found to be considerably smaller than that of structural relaxation.

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^∗: On Leave from Department of Chemistry, Purdue University

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Sequential hypersonic dampings due to fast ion diffusion and structural relaxation in (AgI)x(AgPO3)1−x ionic liquids

Abstract

Solid State Ionics

J. Non-Cryst. Solids

J. Non-Cryst. Solids

Mat. Res. Bull.

Phys. Lett.

Sequential hypersonic dampings due to fast ion diffusion and structural relaxation in (AgI)_x(AgPO₃)_1−x ionic liquids