Materials Data on MgCd2 by Materials Project

Abstract

MgCd2 crystallizes in the orthorhombic Cmcm 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 CdMg6Cd6 cuboctahedra, edges with eight equivalent MgMg2Cd10 cuboctahedra, edges with ten CdMg6Cd6 cuboctahedra, faces with six equivalent MgMg2Cd10 cuboctahedra, and faces with fourteen CdMg6Cd6 cuboctahedra. Both Mg–Mg bond lengths are 3.22 Å. There are a spread of Mg–Cd bond distances ranging from 3.11–3.14 Å. There are two inequivalent Cd sites. In the first Cd site, Cd is bonded to six equivalent Mg and six Cd atoms to form distorted CdMg6Cd6 cuboctahedra that share corners with six equivalent MgMg2Cd10 cuboctahedra, corners with twelve CdMg6Cd6 cuboctahedra, edges with seven equivalent MgMg2Cd10 cuboctahedra, edges with eleven equivalent CdMg4Cd8 cuboctahedra, faces with six equivalent MgMg2Cd10 cuboctahedra, and faces with fourteen CdMg6Cd6 cuboctahedra. There are a spread of Cd–Cd bond distances ranging from 3.10–3.22 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 six equivalent MgMg2Cd10 cuboctahedra, corners with twelve CdMg6Cd6 cuboctahedra, edges with three equivalent MgMg2Cd10 cuboctahedra, edges with fifteen CdMg6Cd6 cuboctahedra, faces with eight equivalent MgMg2Cd10 cuboctahedra, and faces with twelve CdMg6Cd6 cuboctahedra. There are four shorter (3.14 Å) and two longer (3.22 Å) Cd–Cd bond lengths.