Hexagonal perovskites, in contrast to the more familiar perovskites, when oxides, allow for face-sharing of metal–oxygen octahedra or trigonal prisms within their structural frameworks. This results in dimers, trimers, tetramers, or longer fragments of chains of face-sharing octahedra in the crystal structures, and consequently in much shorter metal–metal distances and lower metal–oxygen–metal bond angles than are seen in the more familiar perovskites. The presence of the face-sharing octahedra can have a dramatic impact on magnetic properties of these compounds, and dimer-based materials, in particular, have been the subjects of many quantum-materials-directed studies in materials physics. Hexagonal oxide perovskites are also of contemporary interest due to their potential for geometrical frustration of the ordering of magnetic moments or orbital occupancies at low temperatures, which is especially relevant to their significance as quantum materials. As such, several hexagonal oxide perovskites have been identified as potential candidates for hosting the quantum-spin-liquid state at low temperatures. In our view, hexagonal oxide perovskites are fertile ground for finding new quantum materials. This review briefly describes the solid state chemistry of many of these materials.

中文翻译：

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六角形钙钛矿作为量子材料

与更常见的钙钛矿相比，六角形钙钛矿在氧化物时允许在结构框架内共享金属-氧八面体或三角棱柱的面。这导致晶体结构中的八面体共享面八面体的二聚体，三聚体，四聚体或更长的片段，因此，与更熟悉的钙钛矿相比，金属-金属距离更短，金属-氧-金属键合角更小。共享面部八面体的存在会对这些化合物的磁性产生极大的影响，特别是基于二聚体的材料已经成为许多量子材料指导的材料物理学研究的主题。六方氧化物钙钛矿由于在低温下对磁矩或轨道占有率的排序产生几何挫折的可能性，因此也引起了当代的兴趣，这与它们作为量子材料的意义特别相关。这样，已经鉴定出几种六角形的钙钛矿氧化物是在低温下具有量子自旋液态的潜在候选物。我们认为，六方氧化物钙钛矿是寻找新量子材料的沃土。这篇综述简要描述了其中许多材料的固态化学。我们认为，六方氧化物钙钛矿是寻找新量子材料的沃土。这篇综述简要描述了其中许多材料的固态化学。我们认为，六方氧化物钙钛矿是寻找新量子材料的沃土。这篇综述简要描述了其中许多材料的固态化学。