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DOE OSTI · 1656168

Materials Data on CeZnNi2 by Materials Project

Abstract

CeNi2Zn is Frank-Kasper $\mu$ Phase-derived structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. there are four inequivalent Ce sites. In the first Ce site, Ce is bonded in a 12-coordinate geometry to one Ce, nine equivalent Ni, and three equivalent Zn atoms. The Ce–Ce bond length is 3.34 Å. There are six shorter (2.94 Å) and three longer (3.17 Å) Ce–Ni bond lengths. All Ce–Zn bond lengths are 3.13 Å. In the second Ce site, Ce is bonded in a 12-coordinate geometry to one Ce, nine equivalent Ni, and three equivalent Zn atoms. The Ce–Ce bond length is 3.34 Å. There are six shorter (2.94 Å) and three longer (3.17 Å) Ce–Ni bond lengths. All Ce–Zn bond lengths are 3.13 Å. In the third Ce site, Ce is bonded in a 12-coordinate geometry to one Ce, nine equivalent Ni, and three equivalent Zn atoms. The Ce–Ce bond length is 3.34 Å. There are six shorter (2.94 Å) and three longer (3.17 Å) Ce–Ni bond lengths. All Ce–Zn bond lengths are 3.13 Å. In the fourth Ce site, Ce is bonded in a 6-coordinate geometry to two Ce, twelve equivalent Ni, and six Zn atoms. All Ce–Ni bond lengths are 3.33 Å. All Ce–Zn bond lengths are 3.04 Å. Ni is bonded to five Ce, four equivalent Ni, and three Zn atoms to form distorted NiCe5Zn3Ni4 cuboctahedra that share corners with two equivalent ZnCe6Ni6 cuboctahedra, corners with fifteen equivalent NiCe5Zn3Ni4 cuboctahedra, edges with eight equivalent NiCe5Zn3Ni4 cuboctahedra, faces with three equivalent ZnCe6Ni6 cuboctahedra, and faces with eleven equivalent NiCe5Zn3Ni4 cuboctahedra. There are two shorter (2.61 Å) and two longer (2.66 Å) Ni–Ni bond lengths. There are a spread of Ni–Zn bond distances ranging from 2.53–2.56 Å. There are three inequivalent Zn sites. In the first Zn site, Zn is bonded in a 9-coordinate geometry to three equivalent Ce and six equivalent Ni atoms. In the second Zn site, Zn is bonded in a 9-coordinate geometry to three equivalent Ce and six equivalent Ni atoms. In the third Zn site, Zn is bonded to six Ce and six equivalent Ni atoms to form ZnCe6Ni6 cuboctahedra that share corners with twelve equivalent NiCe5Zn3Ni4 cuboctahedra, edges with six equivalent ZnCe6Ni6 cuboctahedra, and faces with eighteen equivalent NiCe5Zn3Ni4 cuboctahedra.

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2020-07-18. Materials Data on CeZnNi2 by Materials Project. https://doi.org/10.17188/1656168

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