Visualization Method of Ionic Conductivity

无机材料的高温结构测定在基础科学和应用方面都具有越来越重要的意义。高分辨中子粉末衍射是这类研究的有力工具。我们一直在脉冲中子设施KENS开发高分辨率飞行时间（TOF）中子粉末衍射仪（NPD）。采用高分辨率TOF-NPD，获得了高质量的晶体学数据。我们已经成功地使用TOF-NPD进行了高温原位测量。此外，将最大熵法（MEM）成功地应用于TOF- npd数据（TOF/MEM），并通过MEM可视化离子的平均分布。除了平均结构外，离子导体中移动离子的局部结构对理解离子电导率的机理也很重要。从TOF中子衍射数据得到的结构因子S(Q)得到了对分布函数（PDF）和径向分布函数（RDF）。

High temperature structural determination of inorganic materials is more and more important in both basic science and application point of view. High resolution neutron powder diffraction is a powerful tool in such studies. We have been developing high resolution Time-of-Flight (TOF) neutron powder diffractometers (NPD) at the pulsed neutron facility KENS. With using high resolution TOF-NPD, high quality crystallographic data are obtained. We have succeeded in high temperature in situ measurement using TOF-NPD. In addition, Maximum Entropy Method (MEM) is successfully applied to TOF-NPD data (TOF/MEM), and average distribution of ions are visualized by MEM. In addition to average structures, local structures of mobile ions in ionic conductors are also important to understand the mechanism of the ionic conductivity. We have obtained the pair distribution function (PDF) and radial distribution function (RDF) from the structure factor S(Q) obtained from TOF neutron diffraction data.