Big data approach for effective ionic radii

Effective ionic radii are a useful tool for researchers in many disciplines. These radii are usually determined from interatomic distances and the values tabulated by Shannon and Prewitt are widely used since 1969. Here, we present a modern approach based on automated queries to materials databases followed by categorization and tabulation. This method is used to augment the available set of effective ionic radii by providing radii for missing anionic oxidation states and coordination numbers. Our approach proves to yield results that are consistent with known values for anions with well-established oxidation states. More exotic cases result in larger uncertainties due to the smaller amount of available structural data. Nevertheless, the provided estimates give reasonable values for cases that are untabulated at present. Furthermore, our approach is designed to continuously improve together with the growth of available databases. Furthermore, small tweaks of the presented application will allow us to also complement or revise ionic radii of cations. Thus, our approach is designed to update the old and useful concept of effective ionic radii, bringing it to modern days.有效离子半径（effective ionic radii）是众多学科研究人员常用的实用工具。这类半径通常通过原子间距测定，而香农（Shannon）与普里威特（Prewitt）在1969年编制的有效离子半径数值表自推出以来便被广泛采用。本文提出一种基于自动化查询材料数据库，随后开展分类与制表工作的现代化方法。该方法可通过补充缺失的阴离子氧化态与配位数对应的有效离子半径数据，扩充现有的有效离子半径数据集。研究表明，对于氧化态明确的阴离子，本方法得到的结果与已知数值高度一致。但由于可用结构数据相对匮乏，针对更特殊的非常规案例，计算结果的不确定性会相应增大。尽管如此，本方法给出的估算值仍可为当前尚未被收录的案例提供合理的参考数值。此外，本方法可随着材料数据库的持续扩容实现迭代优化。更进一步，对本文所提出的应用工具进行小幅调整，即可实现对阳离子有效离子半径的补充或修正。因此，本方法旨在更新这一成熟实用的有效离子半径概念，使其与时俱进，适配现代研究需求。