论文标题
具有几乎球形分子的塑料晶体中的离子电导率和松弛动力学
Ionic conductivity and relaxation dynamics in plastic-crystals with nearly globular molecules
论文作者
论文摘要
我们已经对塑料晶体1-氰基 - 甲烷（CNA）的离子电荷转运和弛豫动力学进行了介电研究，以及在CNA的两种混合物中与相关的塑料晶体Adamantane或2-腺坦宁中的混合物中。通过添加1％的Li盐提供离子荷载体。这些化合物的分子几乎具有球形形状，因此，假定的所谓的旋转门机制通过其他PC电解质中的分子重新定位促进离子电荷转运，在这里不应活跃。实际上，在研究的PC中，DC电阻率和重新定位α-释放时间的比较揭示了这两种动力学的完全解耦。与其他PC相似，我们发现离子电导率的显着混合诱导的增强。最后，这些固态电解质揭示了第二个弛豫过程，比α-释放速度慢，这与离子跳跃有关。由于上述去耦，因此可以明确检测到它，并且不会被大多数其他离子导体所发现的重新定位贡献叠加。
We have performed a dielectric investigation of the ionic charge transport and the relaxation dynamics in plastic-crystalline 1-cyano-adamantane (CNA) and in two mixtures of CNA with the related plastic crystals adamantane or 2-adamantanon. Ionic charge carriers were provided by adding 1% of Li salt. The molecules of these compounds have nearly globular shape and, thus, the so-called revolving-door mechanism assumed to promote ionic charge transport via molecular reorientations in other PC electrolytes, should not be active here. Indeed, a comparison of the dc resistivity and the reorientational alpha-relaxation times in the investigated PCs, reveals complete decoupling of both dynamics. Similar to other PCs, we find a significant mixing-induced enhancement of the ionic conductivity. Finally, these solid-state electrolytes reveal a second relaxation process, slower than the alpha-relaxation, which is related to ionic hopping. Due to the mentioned decoupling, it can be unequivocally detected and is not superimposed by the reorientational contributions as found for most other ionic conductors.
