In the realm of intermetallic compounds, there is a small group of phases that demonstrate the properties of non-metals. These are intermetallics formed by elements from different blocks of the periodic table, viz., transition metals on the one hand and p-block metals (or metalloids) on the other hand. The interaction between transition metal d-orbitals and p-element s- and p-orbitals leads to the opening of a gap in the band structure, and the Fermi level may fall into the band gap at a certain valence electron concentration, thus providing the non-metallic properties. Despite the lack of a harmonious theory describing the electronic structure of the intermetallics in question, there are approaches that allow one to chemically modify them and thus to design novel thermoelectric materials through the interplay between metals and semiconductors. The review concerns the main families of intermetallic compounds with non-metallic properties. Specific features of their crystal and electronic structures, the reasons for the onset of non-metallic (semiconducting) state, and the prospects for application of these compounds as thermoelectric materials are analyzed.

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具有非金属特性的金属间化合物

在金属间化合物领域，有一小部分相可以显示非金属的特性。这些是由周期表中不同区块的元素形成的金属间化合物，即一方面是过渡金属，另一方面是 p 区金属（或准金属）。过渡金属 d 轨道与 p 元素 s 和 p 轨道之间的相互作用导致带结构中的间隙打开，并且费米能级在一定价电子浓度下可能落入带隙，从而提供非金属特性。尽管缺乏描述相关金属间化合物电子结构的和谐理论，但仍有一些方法可以对它们进行化学修饰，从而通过金属和半导体之间的相互作用设计新型热电材料。审查涉及具有非金属特性的金属间化合物的主要家族。分析了它们的晶体和电子结构的具体特征，非金属（半导体）状态发生的原因，以及这些化合物作为热电材料的应用前景。