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DOE OSTI · 1687145

Materials Data on MgCd5 by Materials Project

Abstract

MgCd5 crystallizes in the monoclinic Cm space group. The structure is three-dimensional. Mg is bonded to two equivalent Mg and ten Cd atoms to form distorted MgMg2Cd10 cuboctahedra that share corners with six equivalent MgMg2Cd10 cuboctahedra, corners with twelve CdMg2Cd10 cuboctahedra, edges with eighteen CdMg2Cd10 cuboctahedra, faces with two equivalent MgMg2Cd10 cuboctahedra, and faces with eighteen CdMg2Cd10 cuboctahedra. Both Mg–Mg bond lengths are 3.20 Å. There are a spread of Mg–Cd bond distances ranging from 3.09–3.20 Å. There are five inequivalent Cd sites. In the first Cd site, Cd is bonded to two equivalent Mg and ten Cd atoms to form distorted CdMg2Cd10 cuboctahedra that share corners with eighteen CdMg2Cd10 cuboctahedra, edges with six equivalent MgMg2Cd10 cuboctahedra, edges with twelve CdMg3Cd9 cuboctahedra, faces with three equivalent MgMg2Cd10 cuboctahedra, and faces with seventeen CdMg2Cd10 cuboctahedra. There are a spread of Cd–Cd bond distances ranging from 3.12–3.22 Å. In the second Cd site, Cd is bonded to three equivalent Mg and nine Cd atoms to form distorted CdMg3Cd9 cuboctahedra that share corners with eighteen CdMg2Cd10 cuboctahedra, edges with two equivalent MgMg2Cd10 cuboctahedra, edges with sixteen CdMg2Cd10 cuboctahedra, faces with five equivalent MgMg2Cd10 cuboctahedra, and faces with fifteen CdMg2Cd10 cuboctahedra. There are a spread of Cd–Cd bond distances ranging from 3.09–3.20 Å. In the third Cd site, Cd is bonded to two equivalent Mg and ten Cd atoms to form distorted CdMg2Cd10 cuboctahedra that share corners with six equivalent MgMg2Cd10 cuboctahedra, corners with twelve CdMg2Cd10 cuboctahedra, edges with three equivalent MgMg2Cd10 cuboctahedra, edges with fifteen CdMg2Cd10 cuboctahedra, faces with three equivalent MgMg2Cd10 cuboctahedra, and faces with seventeen CdMg2Cd10 cuboctahedra. There are a spread of Cd–Cd bond distances ranging from 3.17–3.21 Å. In the fourth Cd site, Cd is bonded to one Mg and eleven Cd atoms to form distorted CdMgCd11 cuboctahedra that share corners with eighteen CdMg2Cd10 cuboctahedra, edges with four equivalent MgMg2Cd10 cuboctahedra, edges with fourteen CdMg2Cd10 cuboctahedra, faces with four equivalent MgMg2Cd10 cuboctahedra, and faces with sixteen CdMg2Cd10 cuboctahedra. There are two shorter (3.18 Å) and two longer (3.20 Å) Cd–Cd bond lengths. In the fifth Cd site, Cd is bonded to two equivalent Mg and ten Cd atoms to form distorted CdMg2Cd10 cuboctahedra that share corners with six equivalent MgMg2Cd10 cuboctahedra, corners with twelve CdMg2Cd10 cuboctahedra, edges with three equivalent MgMg2Cd10 cuboctahedra, edges with fifteen CdMg2Cd10 cuboctahedra, faces with three equivalent MgMg2Cd10 cuboctahedra, and faces with seventeen CdMg2Cd10 cuboctahedra. Both Cd–Cd bond lengths are 3.20 Å.

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2020-05-02. Materials Data on MgCd5 by Materials Project. https://doi.org/10.17188/1687145

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