Müller Peter C, Reitz Linda S, Engel Stefan, Dronskowski Richard, Janka Oliver
Institute of Inorganic Chemistry, RWTH Aachen University, Jülich-Aachen Research Alliance (JARA-CSD), RWTH Aachen University 52056 Aachen Germany.
Inorganic Solid State Chemistry, Saarland University Campus C4.1 66123 Saarbrücken Germany
Chem Sci. 2025 Aug 28. doi: 10.1039/d5sc02993g.
Intermetallic compounds belong to an important class of materials, not only due to the sheer number of compounds known but also due to their application in everyday life. These compounds possess their very own peculiarities, especially when it comes to chemical bonding. To address this point, bonding analyses based on Crystal Orbital Bond Index (COBI) values, Löwdin charges, and - for the first time - oxidation numbers (ON ) were conducted, all extracted from delocalized plane-wave functions. From the integrated COBI values, to be understood as quantum-chemical bond orders, the differences and similarities in the bonding behavior of the elements, binary and ternary compounds in the Ca-Al-Pt system were analyzed. It became apparent that the Al-Pt interactions, almost regardless of the respective compounds, show significant covalency, while Ca-Al and Ca-Pt interactions are of ionic nature in most cases. Homoatomic Al-Al or Pt-Pt interactions, however, tend to be ambivalent, depending on the respective crystal structure of a given compound.
金属间化合物属于一类重要的材料，这不仅是因为已知化合物的数量众多，还因为它们在日常生活中的应用。这些化合物具有其自身的特性，尤其是在化学键方面。为了解决这一问题，基于晶体轨道键指数（COBI）值、洛丁电荷以及首次采用的氧化数（ON）进行了键合分析，所有这些均从离域平面波函数中提取。从综合的COBI值（可理解为量子化学键级）出发，分析了Ca-Al-Pt体系中元素、二元和三元化合物键合行为的差异与相似性。结果表明，几乎无论何种化合物，Al-Pt相互作用都表现出显著的共价性，而Ca-Al和Ca-Pt相互作用在大多数情况下具有离子性质。然而，同原子的Al-Al或Pt-Pt相互作用往往具有矛盾性，这取决于给定化合物的具体晶体结构。
