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DOE OSTI · 1741443

Materials Data on CaCeMg14 by Materials Project

Abstract

CaMg14Ce crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. Ca is bonded to ten Mg and two equivalent Ce atoms to form CaCe2Mg10 cuboctahedra that share corners with six equivalent CaCe2Mg10 cuboctahedra, corners with twelve MgMg12 cuboctahedra, edges with two equivalent CeCa2Mg10 cuboctahedra, edges with sixteen MgCa2Ce2Mg8 cuboctahedra, faces with two equivalent CeCa2Mg10 cuboctahedra, and faces with eighteen MgMg12 cuboctahedra. There are a spread of Ca–Mg bond distances ranging from 3.22–3.31 Å. Both Ca–Ce bond lengths are 3.34 Å. There are thirteen inequivalent Mg sites. In the first Mg site, Mg is bonded to twelve Mg atoms to form MgMg12 cuboctahedra that share corners with four equivalent CeCa2Mg10 cuboctahedra, corners with fourteen MgCa2Ce2Mg8 cuboctahedra, edges with eighteen MgMg12 cuboctahedra, faces with two equivalent CaCe2Mg10 cuboctahedra, and faces with eighteen MgMg12 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.23–3.34 Å. In the second Mg site, Mg is bonded to twelve Mg atoms to form MgMg12 cuboctahedra that share corners with four equivalent CaCe2Mg10 cuboctahedra, corners with fourteen MgCa2Ce2Mg8 cuboctahedra, edges with eighteen MgMg12 cuboctahedra, faces with two equivalent CeCa2Mg10 cuboctahedra, and faces with eighteen MgMg12 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.21–3.27 Å. In the third Mg site, Mg is bonded to two equivalent Ca, eight Mg, and two equivalent Ce atoms to form distorted MgCa2Ce2Mg8 cuboctahedra that share corners with eighteen MgMg12 cuboctahedra, edges with two equivalent CaCe2Mg10 cuboctahedra, edges with two equivalent CeCa2Mg10 cuboctahedra, edges with fourteen MgCa2Ce2Mg8 cuboctahedra, faces with two equivalent CaCe2Mg10 cuboctahedra, faces with two equivalent CeCa2Mg10 cuboctahedra, and faces with sixteen MgMg12 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.24–3.38 Å. There are one shorter (3.23 Å) and one longer (3.30 Å) Mg–Ce bond lengths. In the fourth Mg site, Mg is bonded to twelve Mg atoms to form MgMg12 cuboctahedra that share corners with four equivalent CaCe2Mg10 cuboctahedra, corners with four equivalent CeCa2Mg10 cuboctahedra, corners with ten MgMg12 cuboctahedra, edges with eighteen MgMg12 cuboctahedra, and faces with twenty MgMg12 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.19–3.35 Å. In the fifth Mg site, Mg is bonded to twelve Mg atoms to form MgMg12 cuboctahedra that share corners with four equivalent CaCe2Mg10 cuboctahedra, corners with four equivalent CeCa2Mg10 cuboctahedra, corners with ten MgMg12 cuboctahedra, edges with eighteen MgMg12 cuboctahedra, and faces with twenty MgMg12 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.19–3.35 Å. In the sixth Mg site, Mg is bonded to one Ca, ten Mg, and one Ce atom to form distorted MgCaCeMg10 cuboctahedra that share corners with eighteen MgCeMg11 cuboctahedra, edges with two equivalent CaCe2Mg10 cuboctahedra, edges with two equivalent CeCa2Mg10 cuboctahedra, edges with fourteen MgMg12 cuboctahedra, a faceface with one CaCe2Mg10 cuboctahedra, a faceface with one CeCa2Mg10 cuboctahedra, and faces with eighteen MgMg12 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.23–3.37 Å. The Mg–Ce bond length is 3.27 Å. In the seventh Mg site, Mg is bonded to one Ca, ten Mg, and one Ce atom to form distorted MgCaCeMg10 cuboctahedra that share corners with eighteen MgCaCeMg10 cuboctahedra, edges with two equivalent CaCe2Mg10 cuboctahedra, edges with two equivalent CeCa2Mg10 cuboctahedra, edges with fourteen MgMg12 cuboctahedra, a faceface with one CaCe2Mg10 cuboctahedra, a faceface with one CeCa2Mg10 cuboctahedra, and faces with eighteen MgMg12 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.23–3.37 Å. The Mg–Ce bond length is 3.27 Å. In the eighth Mg site, Mg is bonded to one Ca and eleven Mg atoms to form distorted MgCaMg11 cuboctahedra that share corners with eighteen MgCeMg11 cuboctahedra, edges with two equivalent CaCe2Mg10 cuboctahedra, edges with sixteen MgMg12 cuboctahedra, a faceface with one CaCe2Mg10 cuboctahedra, faces with three equivalent CeCa2Mg10 cuboctahedra, and faces with sixteen MgMg12 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.23–3.34 Å. In the ninth Mg site, Mg is bonded to eleven Mg and one Ce atom to form MgCeMg11 cuboctahedra that share corners with eighteen MgCeMg11 cuboctahedra, edges with two equivalent CeCa2Mg10 cuboctahedra, edges with sixteen MgMg12 cuboctahedra, a faceface with one CeCa2Mg10 cuboctahedra, faces with three equivalent CaCe2Mg10 cuboctahedra, and faces with sixteen MgMg12 cuboctahedra. There are two shorter (3.25 Å) and one longer (3.26 Å) Mg–Mg bond lengths. The Mg–Ce bond length is 3.24 Å. In the tenth Mg site, Mg is bonded to two equivalent Ca, eight Mg, and two equivalent Ce atoms to form distorted MgCa2Ce2Mg8 cuboctahedra that share corners with eighteen MgMg12 cuboctahedra, edges with two equivalent CaCe2Mg10 cuboctahedra, edges with two equivalent CeCa2Mg10 cuboctahedra, edges with fourteen MgCaCeMg10 cuboctahedra, faces with two equivalent CaCe2Mg10 cuboctahedra, faces with two equivalent CeCa2Mg10 cuboctahedra, and faces with sixteen MgCa2Ce2Mg8 cuboctahedra. Both Mg–Mg bond lengths are 3.24 Å. There are one shorter (3.23 Å) and one longer (3.30 Å) Mg–Ce bond lengths. In the eleventh Mg site, Mg is bonded to twelve Mg atoms to form MgMg12 cuboctahedra that share corners with four equivalent CaCe2Mg10 cuboctahedra, corners with four equivalent CeCa2Mg10 cuboctahedra, corners with ten MgCa2Ce2Mg8 cuboctahedra, edges with eighteen MgMg12 cuboctahedra, and faces with twenty MgMg12 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.19–3.25 Å. In the twelfth Mg site, Mg is bonded to twelve Mg atoms to form MgMg12 cuboctahedra that share corners with four equivalent CaCe2Mg10 cuboctahedra, corners with four equivalent CeCa2Mg10 cuboctahedra, corners with ten MgCa2Ce2Mg8 cuboctahedra, edges with eighteen MgMg12 cuboctahedra, and faces with twenty MgMg12 cuboctahedra. Both Mg–Mg bond lengths are 3.19 Å. In the thirteenth Mg site, Mg is bonded to one Ca, ten Mg, and one Ce atom to form distorted MgCaCeMg10 cuboctahedra that share corners with eighteen MgCaCeMg10 cuboctahedra, edges with two equivalent CaCe2Mg10 cuboctahedra, edges with two equivalent CeCa2Mg10 cuboctahedra, edges with fourteen MgMg12 cuboctahedra, a faceface with one CaCe2Mg10 cuboctahedra, a faceface with one CeCa2Mg10 cuboctahedra, and faces with eighteen MgMg12 cuboctahedra. The Mg–Ca bond length is 3.28 Å. There are a spread of Mg–Mg bond distances ranging from 3.21–3.24 Å. The Mg–Ce bond length is 3.27 Å. Ce is bonded to two equivalent Ca and ten Mg atoms to form CeCa2Mg10 cuboctahedra that share corners with six equivalent CeCa2Mg10 cuboctahedra, corners with twelve MgMg12 cuboctahedra, edges with two equivalent CaCe2Mg10 cuboctahedra, edges with sixteen MgCa2Ce2Mg8 cuboctahedra, faces with two equivalent CaCe2Mg10 cuboctahedra, and faces with eighteen MgMg12 cuboctahedra.

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2020-04-29. Materials Data on CaCeMg14 by Materials Project. https://doi.org/10.17188/1741443

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