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 four equivalent Mg and eight Cd atoms to form distorted MgMg4Cd8 cuboctahedra that share corners with six equivalent MgMg4Cd8 cuboctahedra, corners with twelve CdMg3Cd9 cuboctahedra, edges with six equivalent MgMg4Cd8 cuboctahedra, edges with twelve CdMg3Cd9 cuboctahedra, faces with five equivalent MgMg4Cd8 cuboctahedra, and faces with fifteen CdMg3Cd9 cuboctahedra. There are two shorter (3.20 Å) and two longer (3.23 Å) Mg–Mg bond lengths. There are a spread of Mg–Cd bond distances ranging from 3.04–3.22 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 six equivalent MgMg4Cd8 cuboctahedra, corners with twelve CdMg3Cd9 cuboctahedra, edges with seven equivalent MgMg4Cd8 cuboctahedra, edges with eleven CdMg3Cd9 cuboctahedra, faces with seven equivalent MgMg4Cd8 cuboctahedra, and faces with thirteen CdMg3Cd9 cuboctahedra. There are a spread of Cd–Cd bond distances ranging from 3.13–3.21 Å. In the second Cd site, Cd is bonded to five equivalent Mg and seven Cd atoms to form distorted CdMg5Cd7 cuboctahedra that share corners with six equivalent MgMg4Cd8 cuboctahedra, corners with twelve CdMg3Cd9 cuboctahedra, edges with five equivalent MgMg4Cd8 cuboctahedra, edges with thirteen CdMg3Cd9 cuboctahedra, faces with eight equivalent MgMg4Cd8 cuboctahedra, and faces with twelve CdMg3Cd9 cuboctahedra. There are one shorter (3.14 Å) and two longer (3.20 Å) Cd–Cd bond lengths.