Materials Data on Mg6CuSb by Materials Project
Mg6CuSb crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. there are four inequivalent Mg sites. In the first Mg site, Mg is bonded in a 12-coordinate geometry to two equivalent Cu and two equivalent Sb atoms. There are one shorter (3.08 Å) and one longer (3.14 Å) Mg–Cu bond lengths. There are one shorter (3.11 Å) and one longer (3.12 Å) Mg–Sb bond lengths. In the second Mg site, Mg is bonded in a 12-coordinate geometry to two equivalent Cu and two equivalent Sb atoms. Both Mg–Cu bond lengths are 2.98 Å. Both Mg–Sb bond lengths are 3.12 Å. In the third Mg site, Mg is bonded in a distorted water-like geometry to two equivalent Cu atoms. Both Mg–Cu bond lengths are 3.00 Å. In the fourth Mg site, Mg is bonded in a distorted water-like geometry to two equivalent Sb atoms. Both Mg–Sb bond lengths are 3.07 Å. Cu is bonded to ten Mg and two equivalent Sb atoms to form distorted CuMg10Sb2 cuboctahedra that share corners with four equivalent SbMg10Cu2 cuboctahedra, corners with six equivalent CuMg10Sb2 cuboctahedra, edges with two equivalent SbMg10Cu2 cuboctahedra, faces with two equivalent CuMg10Sb2 cuboctahedra, and faces with two equivalent SbMg10Cu2 cuboctahedra. Both Cu–Sb bond lengths are 3.25 Å. Sb is bonded to ten Mg and two equivalent Cu atoms to form distorted SbMg10Cu2 cuboctahedra that share corners with four equivalent CuMg10Sb2 cuboctahedra, corners with six equivalent SbMg10Cu2 cuboctahedra, edges with two equivalent CuMg10Sb2 cuboctahedra, faces with two equivalent CuMg10Sb2 cuboctahedra, and faces with two equivalent SbMg10Cu2 cuboctahedra.