Ion-transport descriptor data for 6,995 Li-, Na-, Mg-, and Al-containing compounds

The geometric crystal structure analysis using three-dimensional Voronoi tessellation could provide the intuitive insights of the ionic transport behavior, and assist to find new solid electrolyte. The existing tools typically consider only the local voids by mapping them with Voronoi polyhedra vertices and define the mobile ions pathways using the Voronoi edges connecting these vertices. However, mobile ions in some structures are located on Voronoi polyhedra faces, and thus cannot be located by this standard approach. To address this deficiency, we extend the method to include Voronoi faces centroids in the constructed network. The effectiveness of our method is demonstrated by ~99% recovery rate for the lattice sites of mobile ions in 6,955 Li-, Na-, Mg- and Al-containing ionic compounds extracted from the Inorganic Crystal Structure Database. <br>The method has been implemented in the python package CAVD (Crystal structure Analysis by Voronoi Decomposition), which is available for the research community on the website of the high-throughput battery materials screening platform (https://www.bmaterials.cn). With the help of CAVD, the calculated descriptors that can be further applied to material machine learning, structure classification and structure–property relationships study, and the visualization files for transport channel (by VESTA4) are also obtained.The ionic transport descriptors recorded in the table have 13 attributes:1. <i>Symmetry_space_group_name_H-M</i>: The name of symmetry space group is extracted from the CIF.<br>2. <i>R_T</i>: The size of restricting interstice or bottleneck in the interstitial network, RT, characterizes the radius of largest ion that can freely pass through the void space.<br>3-5. <i>R_Ta</i>, <i>R_Tb</i>, <i>R_Tc</i>: The RT for three crystallographic directions: <i>R_Ta</i> (a ), <i>R_Tb</i> (b), and <i>R_Tc</i> (c).<br>6. <i>IND</i>: The dimension of the interstitial network. The <i>IND </i>provides the information about the dimensionality of the network that mobile ions can diffuse through in the void space.<br>7. <i>TCD</i>: A list containing the dimension of the connected transport channel. If no connected channels are acquired, the value of <i>TCD</i> is equal to zero. Due to the transport network may consist of more than one transport channel, the dimension of a single channel may differ from the dimension of the transport network.<br>8-10. <i>Acc</i>: The value of <i>Acc_a</i>,<i> Acc_b</i>, and <i>Acc_c </i>can be determined by <i>R_Ta</i>, <i>R_Tb</i>, and <i>R_Tc</i> with threshold, respectively. For example, if <i>R_Ta</i> is greater than threshold, <i>Acc_a</i> = Ture; otherwise, <i>Acc_a</i>= False.<br>11. <i>Recovery status</i>: The mobile ion recovery status for each CIF.<br>12. <i>Ionic_radii</i>: The calculated ionic radii for radical Voronoi decomposition. This value is obtained by combining the rigorous definition of coordination number proposed by O'Keeffe and the table of the effective ionic radii of Shannon.<br>13. <i>Minimal_mobile-framework_distance</i>: The list of minimal mobile-framework distances calculated in different coordination environments. Each item of the list is a tuple, which the first item is a coordination number, and the second item is a distance tuple. The first item of the distance tuple is the distance from the center of mobile ion to the center of nearest framework ion, and the second item is the distance between the center of mobile ion and the surface of nearest framework ion.<br><br><br>

基于三维沃罗诺伊镶嵌（Voronoi tessellation）的晶体几何结构分析，可直观揭示离子输运行为的内在规律，助力新型固体电解质的开发。现有工具通常仅通过将局部空隙与沃罗诺伊多面体顶点进行映射来考量此类空隙，并通过连接这些顶点的沃罗诺伊棱边来定义可迁移离子的传输通道。然而部分结构中的可迁移离子会位于沃罗诺伊多面体的晶面上，因此这类标准方法无法识别此类离子。为解决这一缺陷，本研究将沃罗诺伊面的形心纳入所构建的传输网络中，对原有方法进行了拓展。本方法的有效性通过从无机晶体结构数据库（Inorganic Crystal Structure Database）中提取的6955种含锂、钠、镁、铝的离子化合物的可迁移离子晶格位点约99%的回收率得到了验证。

本方法已被集成至Python工具包CAVD（基于沃罗诺伊分解的晶体结构分析工具，Crystal structure Analysis by Voronoi Decomposition），该工具包可通过高通量电池材料筛选平台官网（https://www.bmaterials.cn）向科研社群开放使用。借助CAVD工具包，用户还可获取可进一步应用于材料机器学习、结构分类以及构效关系研究的计算描述符，以及由VESTA4生成的传输通道可视化文件。

表格中记录的离子输运描述符共包含13项属性：
1. <i>Symmetry_space_group_name_H-M</i>：从晶体信息文件（CIF）中提取的对称空间群名称。
2. <i>R_T</i>：间隙网络中受限空隙或瓶颈的尺寸，即RT，表征可自由通过该空隙空间的最大离子的半径。
3~5. <i>R_Ta</i>、<i>R_Tb</i>、<i>R_Tc</i>：对应三个晶体学方向的RT值，分别为<i>R_Ta</i>（a轴方向）、<i>R_Tb</i>（b轴方向）以及<i>R_Tc</i>（c轴方向）。
6. <i>IND</i>：间隙网络的维度，用于表征可迁移离子在空隙空间中可扩散通过的传输网络的维度信息。
7. <i>TCD</i>：包含连通传输通道维度的列表。若未获取到连通通道，则<i>TCD</i>的值为0。由于传输网络可能包含多条传输通道，单条通道的维度可能与整个传输网络的维度存在差异。
8~10. <i>Acc</i>：<i>Acc_a</i>、<i>Acc_b</i>及<i>Acc_c</i>分别通过阈值结合<i>R_Ta</i>、<i>R_Tb</i>与<i>R_Tc</i>计算得到。例如，若<i>R_Ta</i>大于阈值，则<i>Acc_a</i>为真；反之则为假。
11. <i>Recovery status</i>：对应每份CIF文件的可迁移离子回收率状态。
12. <i>Ionic_radii</i>：基于严格沃罗诺伊分解得到的计算离子半径。该数值结合了奥基夫（O'Keeffe）提出的配位数严谨定义与香农（Shannon）有效离子半径表计算得到。
13. <i>Minimal_mobile-framework_distance</i>：不同配位环境下计算得到的可迁移离子与骨架间最小距离列表。列表中的每一项均为一个元组，其第一个元素为配位数，第二个元素为距离元组；距离元组的第一个元素为可迁移离子中心至最近骨架离子中心的距离，第二个元素为可迁移离子中心至最近骨架离子表面的距离。