Synthesis, Crystal Structure, and Bonding Analysis of the Hypoelectronic Cubic Phase Ca5Pd6Ge6.

Summary, in English

The title compound, Ca5Pd6Ge6, was obtained during a systematic investigation of the Ca-Pd-Ge ternary phase diagram. The crystal structure was determined and refined from single-crystal X-ray diffraction data. It crystallizes in a new structure variant of the Y4PdGa12-type structure (Im3̅m, a = 8.7764(4) Å) that features an arrangement of vertex-sharing body-centered cubes of calcium, Ca@Ca8, with a hierarchical bcc network, interpenetrating a second (Pd6Ge6) network consisting of Ge2 dumbbells surrounded by Pd in a strongly flattened octahedron with Pd(μ(2)-η(2),η(4)-Ge2)-like motifs. These octahedra are condensed through the Pd to form a 3D open fcc network. Theoretical band structure calculations suggested that the compound is hypoelectronic with predominantly multicenter-type interatomic interactions involving all three elements and essentially a Hume-Rothery-like regime of electronic stabilization. The similar electronegativity between germanium and palladium atoms has a decisive impact on the bonding picture of the system.

• Author: Isa Doverbratt; Simeon Ponou; Fei Wang; Sven Lidin
• Department/s: Centre for Analysis and Synthesis
• Publishing year: 2015
• Language: English
• Pages: 9098-9104
• Publication/Series: Inorganic Chemistry
• Volume: 54
• Issue: 18
• Links: http://dx.doi.org/10.1021/acs.inorgchem.5b01528
• Document type: Journal article
• Publisher: The American Chemical Society (ACS)
• Topic: Inorganic Chemistry
• Status: Published
• ISBN/ISSN/Other: ISSN: 1520-510X