Mg14HfC is Hexagonal Laves-derived structured and crystallizes in the hexagonal P-6m2 space group. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 10-coordinate geometry to two equivalent Mg(4) atoms. In the second Mg site, Mg(2) is bonded to two equivalent Mg(4), four equivalent Mg(2), four equivalent Mg(3), and two equivalent Hf(1) atoms to form MgHf2Mg10 cuboctahedra that share corners with six equivalent Mg(2)Hf2Mg10 cuboctahedra, edges with two equivalent Hf(1)Mg12 cuboctahedra, edges with four equivalent Mg(2)Hf2Mg10 cuboctahedra, edges with four equivalent Mg(4)Mg12 cuboctahedra, faces with two equivalent Mg(4)Mg12 cuboctahedra, faces with two equivalent Hf(1)Mg12 cuboctahedra, and faces with four equivalent Mg(2)Hf2Mg10 cuboctahedra. In the third Mg site, Mg(3) is bonded in a 1-coordinate geometry to two equivalent Mg(2), two equivalent Mg(4), one Hf(1), and one C(1) atom. In the fourth Mg site, Mg(4) is bonded to three equivalent Mg(1), three equivalent Mg(2), and six equivalent Mg(3) atoms to form MgMg12 cuboctahedra that share corners with six equivalent Mg(4)Mg12 cuboctahedra, edges with six equivalent Mg(2)Hf2Mg10 cuboctahedra, faces with two equivalent Mg(4)Mg12 cuboctahedra, faces with three equivalent Mg(2)Hf2Mg10 cuboctahedra, and faces with three equivalent Hf(1)Mg12 cuboctahedra. Hf(1) is bonded to six equivalent Mg(2) and six equivalent Mg(3) atoms to form HfMg12 cuboctahedra that share corners with six equivalent Hf(1)Mg12 cuboctahedra, edges with six equivalent Mg(2)Hf2Mg10 cuboctahedra, faces with six equivalent Mg(2)Hf2Mg10 cuboctahedra, and faces with six equivalent Mg(4)Mg12 cuboctahedra. C(1) is bonded in a 6-coordinate geometry to six equivalent Mg(3) atoms.
Mg14HfC is Hexagonal Laves-derived structured and crystallizes in the hexagonal P-6m2 space group. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 10-coordinate geometry to two equivalent Mg(4) atoms. Both Mg(1)-Mg(4) bond lengths are 3.12 Å. In the second Mg site, Mg(2) is bonded to two equivalent Mg(4), four equivalent Mg(2), four equivalent Mg(3), and two equivalent Hf(1) atoms to form MgHf2Mg10 cuboctahedra that share corners with six equivalent Mg(2)Hf2Mg10 cuboctahedra, edges with two equivalent Hf(1)Mg12 cuboctahedra, edges with four equivalent Mg(2)Hf2Mg10 cuboctahedra, edges with four equivalent Mg(4)Mg12 cuboctahedra, faces with two equivalent Mg(4)Mg12 cuboctahedra, faces with two equivalent Hf(1)Mg12 cuboctahedra, and faces with four equivalent Mg(2)Hf2Mg10 cuboctahedra. Both Mg(2)-Mg(4) bond lengths are 3.02 Å. There are two shorter (3.02 Å) and two longer (3.26 Å) Mg(2)-Mg(2) bond lengths. All Mg(2)-Mg(3) bond lengths are 3.19 Å. Both Mg(2)-Hf(1) bond lengths are 3.14 Å. In the third Mg site, Mg(3) is bonded in a 1-coordinate geometry to two equivalent Mg(2), two equivalent Mg(4), one Hf(1), and one C(1) atom. Both Mg(3)-Mg(4) bond lengths are 3.15 Å. The Mg(3)-Hf(1) bond length is 3.11 Å. The Mg(3)-C(1) bond length is 2.87 Å. In the fourth Mg site, Mg(4) is bonded to three equivalent Mg(1), three equivalent Mg(2), and six equivalent Mg(3) atoms to form MgMg12 cuboctahedra that share corners with six equivalent Mg(4)Mg12 cuboctahedra, edges with six equivalent Mg(2)Hf2Mg10 cuboctahedra, faces with two equivalent Mg(4)Mg12 cuboctahedra, faces with three equivalent Mg(2)Hf2Mg10 cuboctahedra, and faces with three equivalent Hf(1)Mg12 cuboctahedra. Hf(1) is bonded to six equivalent Mg(2) and six equivalent Mg(3) atoms to form HfMg12 cuboctahedra that share corners with six equivalent Hf(1)Mg12 cuboctahedra, edges with six equivalent Mg(2)Hf2Mg10 cuboctahedra, faces with six equivalent Mg(2)Hf2Mg10 cuboctahedra, and faces with six equivalent Mg(4)Mg12 cuboctahedra. C(1) is bonded in a 6-coordinate geometry to six equivalent Mg(3) atoms.