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DOE OSTI · 1665534

Materials Data on NbPd4 by Materials Project

Abstract

NbPd4 crystallizes in the trigonal R-3m space group. The structure is three-dimensional. Nb is bonded to six equivalent Nb and six equivalent Pd atoms to form distorted NbNb6Pd6 cuboctahedra that share corners with six equivalent NbNb6Pd6 cuboctahedra, corners with six PdPd12 cuboctahedra, edges with six equivalent NbNb6Pd6 cuboctahedra, edges with eighteen PdNb3Pd9 cuboctahedra, faces with six equivalent NbNb6Pd6 cuboctahedra, and faces with twelve equivalent PdNb3Pd9 cuboctahedra. All Nb–Nb bond lengths are 2.84 Å. All Nb–Pd bond lengths are 2.80 Å. There are eight inequivalent Pd sites. In the first Pd site, Pd is bonded to three equivalent Nb and nine Pd atoms to form distorted PdNb3Pd9 cuboctahedra that share corners with twelve PdNb3Pd9 cuboctahedra, edges with six equivalent NbNb6Pd6 cuboctahedra, edges with eighteen PdNb3Pd9 cuboctahedra, faces with six equivalent NbNb6Pd6 cuboctahedra, and faces with twelve PdNb3Pd9 cuboctahedra. All Pd–Pd bond lengths are 2.84 Å. In the second Pd site, Pd is bonded to twelve Pd atoms to form PdPd12 cuboctahedra that share corners with three equivalent NbNb6Pd6 cuboctahedra, corners with nine PdNb3Pd9 cuboctahedra, edges with three equivalent NbNb6Pd6 cuboctahedra, edges with twenty-one PdNb3Pd9 cuboctahedra, and faces with eighteen PdNb3Pd9 cuboctahedra. There are three shorter (2.82 Å) and six longer (2.84 Å) Pd–Pd bond lengths. In the third Pd site, Pd is bonded to twelve Pd atoms to form PdPd12 cuboctahedra that share corners with three equivalent NbNb6Pd6 cuboctahedra, corners with nine PdNb3Pd9 cuboctahedra, edges with three equivalent NbNb6Pd6 cuboctahedra, edges with twenty-one PdNb3Pd9 cuboctahedra, and faces with eighteen PdNb3Pd9 cuboctahedra. All Pd–Pd bond lengths are 2.84 Å. In the fourth Pd site, Pd is bonded to twelve Pd atoms to form PdPd12 cuboctahedra that share corners with three equivalent NbNb6Pd6 cuboctahedra, corners with nine PdPd12 cuboctahedra, edges with three equivalent NbNb6Pd6 cuboctahedra, edges with twenty-one PdPd12 cuboctahedra, and faces with eighteen PdPd12 cuboctahedra. There are three shorter (2.82 Å) and nine longer (2.84 Å) Pd–Pd bond lengths. In the fifth Pd site, Pd is bonded to twelve Pd atoms to form PdPd12 cuboctahedra that share corners with three equivalent NbNb6Pd6 cuboctahedra, corners with nine PdPd12 cuboctahedra, edges with three equivalent NbNb6Pd6 cuboctahedra, edges with twenty-one PdPd12 cuboctahedra, and faces with eighteen PdPd12 cuboctahedra. All Pd–Pd bond lengths are 2.84 Å. In the sixth Pd site, Pd is bonded to twelve Pd atoms to form PdPd12 cuboctahedra that share corners with three equivalent NbNb6Pd6 cuboctahedra, corners with fourteen PdPd12 cuboctahedra, edges with three equivalent NbNb6Pd6 cuboctahedra, edges with nineteen PdNb3Pd9 cuboctahedra, and faces with twenty-one PdNb3Pd9 cuboctahedra. There are three shorter (2.82 Å) and nine longer (2.84 Å) Pd–Pd bond lengths. In the seventh Pd site, Pd is bonded to sixteen Pd atoms to form PdPd16 cuboctahedra that share corners with three equivalent NbNb6Pd6 cuboctahedra, corners with nineteen PdNb3Pd9 cuboctahedra, edges with three equivalent NbNb6Pd6 cuboctahedra, edges with twenty-one PdNb3Pd9 cuboctahedra, and faces with thirty-four PdPd12 cuboctahedra. There are a spread of Pd–Pd bond distances ranging from 2.84–5.67 Å. In the eighth Pd site, Pd is bonded to three equivalent Nb and nine Pd atoms to form distorted PdNb3Pd9 cuboctahedra that share corners with seventeen PdNb3Pd9 cuboctahedra, edges with six equivalent NbNb6Pd6 cuboctahedra, edges with sixteen PdNb3Pd9 cuboctahedra, faces with six equivalent NbNb6Pd6 cuboctahedra, and faces with fifteen PdPd16 cuboctahedra. All Pd–Nb bond lengths are 2.80 Å. All Pd–Pd bond lengths are 2.84 Å.

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2020-07-20. Materials Data on NbPd4 by Materials Project. https://doi.org/10.17188/1665534

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