Mg6NiSn 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 Ni(1), and two equivalent Sn(1) atoms to form distorted MgMg8Ni2Sn2 cuboctahedra that share corners with four equivalent Ni(1)Mg10Sn2 cuboctahedra, corners with four equivalent Sn(1)Mg10Ni2 cuboctahedra, corners with ten equivalent Mg(1)Mg8Ni2Sn2 cuboctahedra, edges with two equivalent Mg(1)Mg8Ni2Sn2 cuboctahedra, edges with two equivalent Ni(1)Mg10Sn2 cuboctahedra, edges with two equivalent Sn(1)Mg10Ni2 cuboctahedra, faces with two equivalent Ni(1)Mg10Sn2 cuboctahedra, faces with two equivalent Sn(1)Mg10Ni2 cuboctahedra, and faces with four equivalent Mg(1)Mg8Ni2Sn2 cuboctahedra. In the second Mg site, Mg(2) is bonded in a 4-coordinate geometry to two equivalent Mg(1), two equivalent Ni(1), and two equivalent Sn(1) atoms. In the third Mg site, Mg(3) is bonded in a 2-coordinate geometry to four equivalent Mg(1) and two equivalent Ni(1) atoms. In the fourth Mg site, Mg(4) is bonded in a distorted water-like geometry to four equivalent Mg(1) and two equivalent Sn(1) atoms. Ni(1) is bonded to two equivalent Mg(3), four equivalent Mg(1), four equivalent Mg(2), and two equivalent Sn(1) atoms to form distorted NiMg10Sn2 cuboctahedra that share corners with four equivalent Sn(1)Mg10Ni2 cuboctahedra, corners with six equivalent Ni(1)Mg10Sn2 cuboctahedra, corners with eight equivalent Mg(1)Mg8Ni2Sn2 cuboctahedra, edges with two equivalent Sn(1)Mg10Ni2 cuboctahedra, edges with four equivalent Mg(1)Mg8Ni2Sn2 cuboctahedra, faces with two equivalent Ni(1)Mg10Sn2 cuboctahedra, faces with two equivalent Sn(1)Mg10Ni2 cuboctahedra, and faces with four equivalent Mg(1)Mg8Ni2Sn2 cuboctahedra. Sn(1) is bonded to two equivalent Mg(4), four equivalent Mg(1), four equivalent Mg(2), and two equivalent Ni(1) atoms to form distorted SnMg10Ni2 cuboctahedra that share corners with four equivalent Ni(1)Mg10Sn2 cuboctahedra, corners with six equivalent Sn(1)Mg10Ni2 cuboctahedra, corners with eight equivalent Mg(1)Mg8Ni2Sn2 cuboctahedra, edges with two equivalent Ni(1)Mg10Sn2 cuboctahedra, edges with four equivalent Mg(1)Mg8Ni2Sn2 cuboctahedra, faces with two equivalent Ni(1)Mg10Sn2 cuboctahedra, faces with two equivalent Sn(1)Mg10Ni2 cuboctahedra, and faces with four equivalent Mg(1)Mg8Ni2Sn2 cuboctahedra.
Mg6NiSn 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 Ni(1), and two equivalent Sn(1) atoms to form distorted MgMg8Ni2Sn2 cuboctahedra that share corners with four equivalent Ni(1)Mg10Sn2 cuboctahedra, corners with four equivalent Sn(1)Mg10Ni2 cuboctahedra, corners with ten equivalent Mg(1)Mg8Ni2Sn2 cuboctahedra, edges with two equivalent Mg(1)Mg8Ni2Sn2 cuboctahedra, edges with two equivalent Ni(1)Mg10Sn2 cuboctahedra, edges with two equivalent Sn(1)Mg10Ni2 cuboctahedra, faces with two equivalent Ni(1)Mg10Sn2 cuboctahedra, faces with two equivalent Sn(1)Mg10Ni2 cuboctahedra, and faces with four equivalent Mg(1)Mg8Ni2Sn2 cuboctahedra. There is one shorter (3.11 Å) and one longer (3.16 Å) Mg(1)-Mg(1) bond length. Both Mg(1)-Mg(2) bond lengths are 3.05 Å. Both Mg(1)-Mg(3) bond lengths are 3.05 Å. Both Mg(1)-Mg(4) bond lengths are 3.03 Å. There is one shorter (3.08 Å) and one longer (3.11 Å) Mg(1)-Ni(1) bond length. There is one shorter (3.08 Å) and one longer (3.11 Å) Mg(1)-Sn(1) bond length. In the second Mg site, Mg(2) is bonded in a 4-coordinate geometry to two equivalent Mg(1), two equivalent Ni(1), and two equivalent Sn(1) atoms. Both Mg(2)-Ni(1) bond lengths are 2.97 Å. Both Mg(2)-Sn(1) bond lengths are 3.08 Å. In the third Mg site, Mg(3) is bonded in a 2-coordinate geometry to four equivalent Mg(1) and two equivalent Ni(1) atoms. Both Mg(3)-Ni(1) bond lengths are 2.97 Å. In the fourth Mg site, Mg(4) is bonded in a distorted water-like geometry to four equivalent Mg(1) and two equivalent Sn(1) atoms. Both Mg(4)-Sn(1) bond lengths are 3.03 Å. Ni(1) is bonded to two equivalent Mg(3), four equivalent Mg(1), four equivalent Mg(2), and two equivalent Sn(1) atoms to form distorted NiMg10Sn2 cuboctahedra that share corners with four equivalent Sn(1)Mg10Ni2 cuboctahedra, corners with six equivalent Ni(1)Mg10Sn2 cuboctahedra, corners with eight equivalent Mg(1)Mg8Ni2Sn2 cuboctahedra, edges with two equivalent Sn(1)Mg10Ni2 cuboctahedra, edges with four equivalent Mg(1)Mg8Ni2Sn2 cuboctahedra, faces with two equivalent Ni(1)Mg10Sn2 cuboctahedra, faces with two equivalent Sn(1)Mg10Ni2 cuboctahedra, and faces with four equivalent Mg(1)Mg8Ni2Sn2 cuboctahedra. Both Ni(1)-Sn(1) bond lengths are 3.13 Å. Sn(1) is bonded to two equivalent Mg(4), four equivalent Mg(1), four equivalent Mg(2), and two equivalent Ni(1) atoms to form distorted SnMg10Ni2 cuboctahedra that share corners with four equivalent Ni(1)Mg10Sn2 cuboctahedra, corners with six equivalent Sn(1)Mg10Ni2 cuboctahedra, corners with eight equivalent Mg(1)Mg8Ni2Sn2 cuboctahedra, edges with two equivalent Ni(1)Mg10Sn2 cuboctahedra, edges with four equivalent Mg(1)Mg8Ni2Sn2 cuboctahedra, faces with two equivalent Ni(1)Mg10Sn2 cuboctahedra, faces with two equivalent Sn(1)Mg10Ni2 cuboctahedra, and faces with four equivalent Mg(1)Mg8Ni2Sn2 cuboctahedra.