We present a range of inverse perovskite nitrides with an elpasolite-type superstructure. (CaN)Sn and (CaN)Pb are variants of the previously described (CaN)Sn and (CaN)Pb which contain less nitrogen and crystallize in . (BaN)Sn and (BaN)Pb resemble the previously reported perovskites (BaN)Sn and (BaN)Pb, but with both the superstructure and octahedral tilting, resulting in space group . (CaN)Si, (CaN)Ge, (SrN)Ge and (BaN)Ge all crystallize in 2/. Among these, only (CaN)Ge has been previously described as (CaN)Ge. (CaN)Si is notably the first compound in which mutually isolated N and Si ions coexist. There also exists a version with composition (CaN)Si, which crystallizes in the cubic perovskite aristotype structure with space group . Similarly, there are versions of (SrN)Ge, (BaN)Sn and (BaN)Pb with elevated nitrogen contents, less strongly tilted octahedra and no apparent superstructure. Electronic structure calculations indicate a metallic nature of the title compounds, with rather narrow improper band gaps for the strontium and barium compounds.

中文翻译：

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反钙钛矿氮化物中的钾冰晶石型超结构

我们提出了一系列具有钾冰晶石型上部结构的反钙钛矿氮化物。(CaN)Sn和(CaN)Pb是先前描述的(CaN)Sn和(CaN)Pb的变体，其含有较少的氮并结晶。(BaN)Sn 和 (BaN)Pb 类似于先前报道的钙钛矿 (BaN)Sn 和 (BaN)Pb，但具有超结构和八面体倾斜，从而产生空间群。(CaN)Si、(CaN)Ge、(SrN)Ge和(BaN)Ge均以2/结晶。其中，只有(CaN)Ge先前被描述为(CaN)Ge。(CaN)Si 是第一种相互孤立的 N 离子和 Si 离子共存的化合物。还有一种成分为 (CaN)Si 的版本，其结晶为具有空间群的立方钙钛矿亚里斯多型结构。类似地，(SrN)Ge、(BaN)Sn 和 (BaN)Pb 的氮含量较高、八面体倾斜度较小且没有明显的超结构。电子结构计算表明标题化合物具有金属性质，锶和钡化合物具有相当窄的不适当带隙。