Abstract Compounds that contain two types of anion are attracting attention as a new field of solid state chemistry. The nitride anion is similar to the oxide anion in size and nature. They coordinate together to cations in oxynitrides to form characteristic local structures around them in a certain way. Special properties induced by the specific local structure have been observed in oxynitrides. Ferroelectricity was identified in oxynitride perovskites, especially those of tantalum, because the oxide and nitride anions form a polar ordered local crystal structure around Ta 5+ in the 5d 0 electron configuration. The critical current density in superconductivity was enhanced by the formation of clusters in niobium oxynitrides with the rocksalt-type structure. Main group elements doped into the niobium oxynitrides, especially silicon, are coordinated mainly by oxides with some amount of nitrides to form silicon oxide-like clusters. The niobium in the oxynitride has some 4d electrons to maintain the superconductivity in the niobium oxynitride host. Here, the preparation, crystal structure and properties of oxynitrides formed with tantalum and niobium are reviewed.

中文翻译：

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钽和铌氧氮化物中局部结构的显着影响

摘要 含有两种阴离子的化合物作为固态化学的一个新领域而备受关注。氮化物阴离子在大小和性质上与氧化物阴离子相似。它们与氮氧化物中的阳离子协同配合，以某种方式在它们周围形成特征性的局部结构。在氮氧化物中观察到由特定局部结构引起的特殊性质。在氧氮化物钙钛矿中发现了铁电性，尤其是钽的那些，因为氧化物和氮化物阴离子在 5d 0 电子配置中围绕 Ta 5+ 形成极性有序的局部晶体结构。超导中的临界电流密度通过在具有岩盐型结构的铌氮氧化物中形成团簇而得到增强。掺入铌氮氧化物的主族元素，尤其是硅，主要由氧化物与一定量的氮化物配位形成氧化硅类簇。氮氧化物中的铌具有一些 4d 电子，以维持铌氧氮化物主体中的超导性。本文综述了钽和铌形成的氮氧化物的制备、晶体结构和性质。