Obtaining a better understanding of activation volumes in ionic conductors

超离子导体是一种类似于液体电解液的快速离子传导材料，目前正在研究用于固态电池。超离子导体通常通过依赖温度的测量来研究，目的是评估离子跃迁的活化能和能垒。虽然这种方法已经成功地获得了离子输运的一般特征，但人们对离子跃迁的潜在结构现象还没有很好的理解。相反，测量离子电导率的压力依赖关系可以得到另一个热力学参数，即活化体积。激活体积描述了一个结构需要在多大程度上局部扭曲才能使离子跃迁发生。然而，虽然这种热力学性质通常是已知的，但对于晶体结构和引起的结构变化如何影响活化体积还缺乏深入的了解和描述。因此，该提议试图从根本上更好地理解快子导体的压力依赖性以及晶体结构和活化体之间的相互作用。

Superionic conductors are materials that provide fast ion conduction similar to liquid electrolytes, and are currently investigated for the use in solid-state batteries. Superionic conductors are usually investigated by temperature – dependent measurements with the goal to assess the activation energies and energetic barriers for the ionic jump. Whereas this approach has been successful in obtaining general characteristics of ion transport, the underlying structural phenomena of an ion jump are not well understood.In contrast, measuring the pressure – dependence of the ionic conductivity leads to another thermodynamic parameter, the activation volume. The activation volume describes how much a structure needs to distort locally to let an ion jump occur. However, while this thermodynamic property is known in general, an in depth understanding and description is missing in how a crystal structure and induced structural changes may affect the activation volume. Therefore, the proposal seeks to obtain a better fundamental understanding of the pressure – dependence of superionic conductors and the interplay between crystal structure and the activation volume.