In this Account, we focused on a unique class of inclusion compounds, intermetallic clathrates, which exist in a variety of structures and exhibit diverse physical properties. These compounds combine covalent tetrahedral frameworks with rattling guest atoms situated inside their framework cages. Tetrels, the group 14 elements, are the basis for conventional clathrates because they fulfill the bonding requirement of four electrons per framework atom. In analogy to the replacement of Ge with GaAs in semiconductors, we focused on unconventional tetrel-free clathrates with frameworks composed of phosphorus and late transition metals. Compared to tetrels, these elements exhibit greater flexibility in their local coordinations and bonding. Tetrel elements cannot tolerate high deviations from regular tetrahedral coordinations. Thus, they exile a number of theoretically predicted framework topologies that are composed of a single type of polyhedral cage with square faces, such as the truncated octahedron. Unconventional clathrates are capable of stabilizing both envisaged and unique, unforeseen topologies.

中文翻译：

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过渡金属-磷骨架的非常规包合物

在本报告中，我们重点研究了独特的一类夹杂物，金属间包合物，它们以各种结构存在并表现出多种物理性质。这些化合物将共价四面体骨架与位于其骨架笼中的棘手的来宾原子结合在一起。锡rel（第14组元素）是常规包合物的基础，因为它们满足每个骨架原子四个电子的键合要求。与在半导体中用GaAs替代Ge类似，我们重点研究了具有由磷和后期过渡金属组成的骨架的非常规无et石笼形包合物。与t相比，这些元素在其局部配位和键合方面表现出更大的灵活性。Tetrel元素不能忍受常规四面体配位的高偏差。因此，他们放逐了许多在理论上预测的框架拓扑，这些拓扑由具有正方形面的单一类型的多面体笼组成，例如截短的八面体。非常规包合物能够稳定设想的和独特的，不可预见的拓扑。