Materials Data on Mg6CuSn by Materials Project
Mg6CuSn 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 to eight Mg, two equivalent Cu, and two equivalent Sn atoms to form distorted MgMg8Cu2Sn2 cuboctahedra that share corners with four equivalent CuMg10Sn2 cuboctahedra, corners with four equivalent SnMg10Cu2 cuboctahedra, corners with fourteen MgMg8Cu2Sn2 cuboctahedra, edges with two equivalent CuMg10Sn2 cuboctahedra, edges with two equivalent SnMg10Cu2 cuboctahedra, edges with four MgMg8Cu2Sn2 cuboctahedra, faces with two equivalent CuMg10Sn2 cuboctahedra, faces with two equivalent SnMg10Cu2 cuboctahedra, and faces with four equivalent MgMg8Cu2Sn2 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.06–3.18 Å. There are one shorter (3.11 Å) and one longer (3.13 Å) Mg–Cu bond lengths. There are one shorter (3.12 Å) and one longer (3.13 Å) Mg–Sn bond lengths. In the second Mg site, Mg is bonded in a 12-coordinate geometry to two equivalent Mg, two equivalent Cu, and two equivalent Sn atoms. Both Mg–Cu bond lengths are 3.03 Å. Both Mg–Sn bond lengths are 3.10 Å. In the third Mg site, Mg is bonded to four equivalent Mg and two equivalent Cu atoms to form distorted MgMg4Cu2 cuboctahedra that share corners with four equivalent CuMg10Sn2 cuboctahedra, corners with eight equivalent MgMg8Cu2Sn2 cuboctahedra, edges with two equivalent CuMg10Sn2 cuboctahedra, edges with four equivalent MgMg8Cu2Sn2 cuboctahedra, edges with six equivalent SnMg10Cu2 cuboctahedra, and faces with two equivalent MgMg4Cu2 cuboctahedra. Both Mg–Cu bond lengths are 3.02 Å. In the fourth Mg site, Mg is bonded in a distorted water-like geometry to four equivalent Mg and two equivalent Sn atoms. Both Mg–Sn bond lengths are 3.06 Å. Cu is bonded to ten Mg and two equivalent Sn atoms to form CuMg10Sn2 cuboctahedra that share corners with four equivalent SnMg10Cu2 cuboctahedra, corners with six equivalent CuMg10Sn2 cuboctahedra, corners with twelve MgMg8Cu2Sn2 cuboctahedra, edges with two equivalent SnMg10Cu2 cuboctahedra, edges with six MgMg8Cu2Sn2 cuboctahedra, faces with two equivalent CuMg10Sn2 cuboctahedra, faces with two equivalent SnMg10Cu2 cuboctahedra, and faces with four equivalent MgMg8Cu2Sn2 cuboctahedra. Both Cu–Sn bond lengths are 3.17 Å. Sn is bonded to ten Mg and two equivalent Cu atoms to form SnMg10Cu2 cuboctahedra that share corners with four equivalent CuMg10Sn2 cuboctahedra, corners with six equivalent SnMg10Cu2 cuboctahedra, corners with eight equivalent MgMg8Cu2Sn2 cuboctahedra, edges with two equivalent CuMg10Sn2 cuboctahedra, edges with ten MgMg8Cu2Sn2 cuboctahedra, faces with two equivalent CuMg10Sn2 cuboctahedra, faces with two equivalent SnMg10Cu2 cuboctahedra, and faces with four equivalent MgMg8Cu2Sn2 cuboctahedra.