Relaxation dynamics and ionic conductivity in a fragile plastic crystal

Th. Bauer; M. Köhler; P. Lunkenheimer; A. Loidl; C. A. Angell

doi:10.1063/1.3487521

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arXiv · 1006.5930

Relaxation dynamics and ionic conductivity in a fragile plastic crystal

Th. Bauer·M. Köhler·P. Lunkenheimer·A. Loidl·C. A. Angell

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Abstract

We report a thorough characterization of the dielectric relaxation behavior and the ionic conductivity in the plastic-crystalline mixture of 60% succinonitrile and 40% glutaronitrile. The plastic phase can be easily supercooled and the relaxational behavior is investigated by broadband dielectric spectroscopy in the liquid, plastic crystalline, and glassy crystal phases. The very pronounced alpha-relaxation found in the spectra is characterized in detail. From the temperature dependence of the alpha-relaxation time, a fragility parameter of 62 was determined making this material one of the most fragile plastic-crystalline glass formers. A well-pronounced secondary and faint indications for a third relaxation process were found, the latter most likely being of Johari-Goldstein type. In addition, relatively strong conductivity contributions were detected in the spectra exhibiting the typical features of ionic charge transport.

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Th. Bauer, M. Köhler, P. Lunkenheimer, A. Loidl, C. A. Angell. 2010-06-30. Relaxation dynamics and ionic conductivity in a fragile plastic crystal. https://doi.org/10.1063/1.3487521

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