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DOE OSTI · 1685439

Materials Data on MgCd2 by Materials Project

Abstract

MgCd2 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. Mg is bonded to seven Cd atoms to form distorted MgCd7 cuboctahedra that share corners with twenty-one CdMg3Cd9 cuboctahedra, edges with four equivalent MgCd7 cuboctahedra, edges with seventeen CdMg3Cd9 cuboctahedra, a faceface with one CdMg3Cd9 cuboctahedra, and faces with three equivalent MgCd7 cuboctahedra. There are a spread of Mg–Cd bond distances ranging from 3.07–3.12 Å. There are two inequivalent Cd sites. In the first Cd site, Cd is bonded to three equivalent Mg and nine Cd atoms to form distorted CdMg3Cd9 cuboctahedra that share corners with ten equivalent MgCd7 cuboctahedra, corners with twelve CdMg3Cd9 cuboctahedra, edges with nine equivalent MgCd7 cuboctahedra, edges with eleven CdMg3Cd9 cuboctahedra, a faceface with one MgCd7 cuboctahedra, and faces with thirteen CdMg3Cd9 cuboctahedra. There are a spread of Cd–Cd bond distances ranging from 3.17–3.23 Å. In the second Cd site, Cd is bonded to four equivalent Mg and eight Cd atoms to form distorted CdMg4Cd8 cuboctahedra that share corners with eleven equivalent MgCd7 cuboctahedra, corners with twelve CdMg3Cd9 cuboctahedra, edges with eight equivalent MgCd7 cuboctahedra, edges with nine CdMg3Cd9 cuboctahedra, and faces with fourteen CdMg3Cd9 cuboctahedra. There are one shorter (3.15 Å) and two longer (3.19 Å) Cd–Cd bond lengths.

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2020-05-04. Materials Data on MgCd2 by Materials Project. https://doi.org/10.17188/1685439

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36 MATERIALS SCIENCE↗