Mg6ZnSi crystallizes in the orthorhombic Amm2 space group. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), two equivalent Zn(1), and two equivalent Si(1) atoms to form distorted MgMg8Zn2Si2 cuboctahedra that share corners with ten equivalent Mg(1)Mg8Zn2Si2 cuboctahedra, edges with two equivalent Mg(1)Mg8Zn2Si2 cuboctahedra, edges with four equivalent Mg(3)Mg10Zn2 cuboctahedra, faces with two equivalent Mg(3)Mg10Zn2 cuboctahedra, and faces with four equivalent Mg(1)Mg8Zn2Si2 cuboctahedra. In the second Mg site, Mg(2) is bonded in a 4-coordinate geometry to two equivalent Mg(1), two equivalent Mg(3), two equivalent Zn(1), and two equivalent Si(1) atoms. In the third Mg site, Mg(3) is bonded to two equivalent Mg(4), four equivalent Mg(1), four equivalent Mg(2), and two equivalent Zn(1) atoms to form distorted MgMg10Zn2 cuboctahedra that share corners with six equivalent Mg(3)Mg10Zn2 cuboctahedra, edges with eight equivalent Mg(1)Mg8Zn2Si2 cuboctahedra, faces with two equivalent Mg(3)Mg10Zn2 cuboctahedra, and faces with four equivalent Mg(1)Mg8Zn2Si2 cuboctahedra. In the fourth Mg site, Mg(4) is bonded in a distorted water-like geometry to two equivalent Mg(3), four equivalent Mg(1), and two equivalent Si(1) atoms. Zn(1) is bonded in a distorted q6 geometry to two equivalent Mg(3), four equivalent Mg(1), and four equivalent Mg(2) atoms. Si(1) is bonded in a distorted q6 geometry to two equivalent Mg(4), four equivalent Mg(1), and four equivalent Mg(2) atoms.
Mg6ZnSi crystallizes in the orthorhombic Amm2 space group. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), two equivalent Zn(1), and two equivalent Si(1) atoms to form distorted MgMg8Zn2Si2 cuboctahedra that share corners with ten equivalent Mg(1)Mg8Zn2Si2 cuboctahedra, edges with two equivalent Mg(1)Mg8Zn2Si2 cuboctahedra, edges with four equivalent Mg(3)Mg10Zn2 cuboctahedra, faces with two equivalent Mg(3)Mg10Zn2 cuboctahedra, and faces with four equivalent Mg(1)Mg8Zn2Si2 cuboctahedra. There is one shorter (3.21 Å) and one longer (3.23 Å) Mg(1)-Mg(1) bond length. Both Mg(1)-Mg(2) bond lengths are 3.01 Å. Both Mg(1)-Mg(3) bond lengths are 3.03 Å. Both Mg(1)-Mg(4) bond lengths are 3.03 Å. There is one shorter (3.05 Å) and one longer (3.08 Å) Mg(1)-Zn(1) bond length. Both Mg(1)-Si(1) bond lengths are 3.06 Å. In the second Mg site, Mg(2) is bonded in a 4-coordinate geometry to two equivalent Mg(1), two equivalent Mg(3), two equivalent Zn(1), and two equivalent Si(1) atoms. There is one shorter (2.99 Å) and one longer (3.13 Å) Mg(2)-Mg(3) bond length. Both Mg(2)-Zn(1) bond lengths are 3.01 Å. Both Mg(2)-Si(1) bond lengths are 3.02 Å. In the third Mg site, Mg(3) is bonded to two equivalent Mg(4), four equivalent Mg(1), four equivalent Mg(2), and two equivalent Zn(1) atoms to form distorted MgMg10Zn2 cuboctahedra that share corners with six equivalent Mg(3)Mg10Zn2 cuboctahedra, edges with eight equivalent Mg(1)Mg8Zn2Si2 cuboctahedra, faces with two equivalent Mg(3)Mg10Zn2 cuboctahedra, and faces with four equivalent Mg(1)Mg8Zn2Si2 cuboctahedra. Both Mg(3)-Mg(4) bond lengths are 3.22 Å. Both Mg(3)-Zn(1) bond lengths are 2.96 Å. In the fourth Mg site, Mg(4) is bonded in a distorted water-like geometry to two equivalent Mg(3), four equivalent Mg(1), and two equivalent Si(1) atoms. Both Mg(4)-Si(1) bond lengths are 2.96 Å. Zn(1) is bonded in a distorted q6 geometry to two equivalent Mg(3), four equivalent Mg(1), and four equivalent Mg(2) atoms. Si(1) is bonded in a distorted q6 geometry to two equivalent Mg(4), four equivalent Mg(1), and four equivalent Mg(2) atoms.