CaMg14Co crystallizes in the orthorhombic Amm2 space group. Ca(1) is bonded to two equivalent Mg(6), four equivalent Mg(3), four equivalent Mg(5), and two equivalent Co(1) atoms to form CaMg10Co2 cuboctahedra that share corners with four equivalent Mg(2)Mg12 cuboctahedra, corners with six equivalent Ca(1)Mg10Co2 cuboctahedra, corners with eight equivalent Mg(4)Mg12 cuboctahedra, edges with four equivalent Mg(6)CaMg11 cuboctahedra, faces with two equivalent Mg(6)CaMg11 cuboctahedra, and faces with two equivalent Mg(1)Mg12 cuboctahedra. There are seven inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent Mg(2), two equivalent Mg(6), four equivalent Mg(4), and four equivalent Mg(5) atoms to form MgMg12 cuboctahedra that share corners with six equivalent Mg(1)Mg12 cuboctahedra, edges with two equivalent Mg(2)Mg12 cuboctahedra, edges with four equivalent Mg(6)CaMg11 cuboctahedra, edges with four equivalent Mg(4)Mg12 cuboctahedra, faces with two equivalent Ca(1)Mg10Co2 cuboctahedra, faces with two equivalent Mg(6)CaMg11 cuboctahedra, faces with two equivalent Mg(2)Mg12 cuboctahedra, and faces with four equivalent Mg(4)Mg12 cuboctahedra. In the second Mg site, Mg(2) is bonded to two equivalent Mg(1), two equivalent Mg(7), four equivalent Mg(4), and four equivalent Mg(5) atoms to form MgMg12 cuboctahedra that share corners with four equivalent Ca(1)Mg10Co2 cuboctahedra, corners with six equivalent Mg(2)Mg12 cuboctahedra, edges with two equivalent Mg(1)Mg12 cuboctahedra, edges with four equivalent Mg(4)Mg12 cuboctahedra, faces with two equivalent Mg(1)Mg12 cuboctahedra, faces with four equivalent Mg(4)Mg12 cuboctahedra, and faces with six equivalent Mg(6)CaMg11 cuboctahedra. In the third Mg site, Mg(3) is bonded in a 1-coordinate geometry to two equivalent Ca(1), two equivalent Mg(5), two equivalent Mg(6), and one Co(1) atom. In the fourth Mg site, Mg(4) is bonded to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(4), two equivalent Mg(5), two equivalent Mg(6), and two equivalent Mg(7) atoms to form MgMg12 cuboctahedra that share corners with four equivalent Ca(1)Mg10Co2 cuboctahedra, corners with six equivalent Mg(4)Mg12 cuboctahedra, edges with two equivalent Mg(1)Mg12 cuboctahedra, edges with two equivalent Mg(2)Mg12 cuboctahedra, edges with two equivalent Mg(4)Mg12 cuboctahedra, edges with four equivalent Mg(6)CaMg11 cuboctahedra, faces with two equivalent Mg(6)CaMg11 cuboctahedra, faces with two equivalent Mg(1)Mg12 cuboctahedra, faces with two equivalent Mg(2)Mg12 cuboctahedra, and faces with two equivalent Mg(4)Mg12 cuboctahedra. In the fifth Mg site, Mg(5) is bonded in a 12-coordinate geometry to one Ca(1), one Mg(1), one Mg(2), one Mg(3), one Mg(4), two equivalent Mg(5), two equivalent Mg(6), two equivalent Mg(7), and one Co(1) atom. In the sixth Mg site, Mg(6) is bonded to one Ca(1), one Mg(1), two equivalent Mg(3), two equivalent Mg(4), two equivalent Mg(7), and four equivalent Mg(5) atoms to form distorted MgCaMg11 cuboctahedra that share corners with six equivalent Mg(6)CaMg11 cuboctahedra, edges with two equivalent Ca(1)Mg10Co2 cuboctahedra, edges with two equivalent Mg(1)Mg12 cuboctahedra, edges with four equivalent Mg(4)Mg12 cuboctahedra,  a faceface with one Ca(1)Mg10Co2 cuboctahedra,  a faceface with one Mg(1)Mg12 cuboctahedra, faces with two equivalent Mg(6)CaMg11 cuboctahedra, faces with two equivalent Mg(4)Mg12 cuboctahedra, and faces with three equivalent Mg(2)Mg12 cuboctahedra. In the seventh Mg site, Mg(7) is bonded in a distorted single-bond geometry to one Mg(2), two equivalent Mg(4), two equivalent Mg(6), four equivalent Mg(5), and one Co(1) atom. Co(1) is bonded in a 10-coordinate geometry to two equivalent Ca(1), two equivalent Mg(3), two equivalent Mg(7), and four equivalent Mg(5) atoms.
CaMg14Co crystallizes in the orthorhombic Amm2 space group. Ca(1) is bonded to two equivalent Mg(6), four equivalent Mg(3), four equivalent Mg(5), and two equivalent Co(1) atoms to form CaMg10Co2 cuboctahedra that share corners with four equivalent Mg(2)Mg12 cuboctahedra, corners with six equivalent Ca(1)Mg10Co2 cuboctahedra, corners with eight equivalent Mg(4)Mg12 cuboctahedra, edges with four equivalent Mg(6)CaMg11 cuboctahedra, faces with two equivalent Mg(6)CaMg11 cuboctahedra, and faces with two equivalent Mg(1)Mg12 cuboctahedra. Both Ca(1)-Mg(6) bond lengths are 3.20 Å. There are two shorter (3.22 Å) and two longer (3.23 Å) Ca(1)-Mg(3) bond lengths. All Ca(1)-Mg(5) bond lengths are 3.19 Å. Both Ca(1)-Co(1) bond lengths are 3.14 Å. There are seven inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent Mg(2), two equivalent Mg(6), four equivalent Mg(4), and four equivalent Mg(5) atoms to form MgMg12 cuboctahedra that share corners with six equivalent Mg(1)Mg12 cuboctahedra, edges with two equivalent Mg(2)Mg12 cuboctahedra, edges with four equivalent Mg(6)CaMg11 cuboctahedra, edges with four equivalent Mg(4)Mg12 cuboctahedra, faces with two equivalent Ca(1)Mg10Co2 cuboctahedra, faces with two equivalent Mg(6)CaMg11 cuboctahedra, faces with two equivalent Mg(2)Mg12 cuboctahedra, and faces with four equivalent Mg(4)Mg12 cuboctahedra. Both Mg(1)-Mg(2) bond lengths are 3.13 Å. Both Mg(1)-Mg(6) bond lengths are 3.06 Å. There are two shorter (3.17 Å) and two longer (3.27 Å) Mg(1)-Mg(4) bond lengths. All Mg(1)-Mg(5) bond lengths are 3.18 Å. In the second Mg site, Mg(2) is bonded to two equivalent Mg(1), two equivalent Mg(7), four equivalent Mg(4), and four equivalent Mg(5) atoms to form MgMg12 cuboctahedra that share corners with four equivalent Ca(1)Mg10Co2 cuboctahedra, corners with six equivalent Mg(2)Mg12 cuboctahedra, edges with two equivalent Mg(1)Mg12 cuboctahedra, edges with four equivalent Mg(4)Mg12 cuboctahedra, faces with two equivalent Mg(1)Mg12 cuboctahedra, faces with four equivalent Mg(4)Mg12 cuboctahedra, and faces with six equivalent Mg(6)CaMg11 cuboctahedra. Both Mg(2)-Mg(7) bond lengths are 3.30 Å. There are two shorter (3.20 Å) and two longer (3.24 Å) Mg(2)-Mg(4) bond lengths. All Mg(2)-Mg(5) bond lengths are 3.14 Å. In the third Mg site, Mg(3) is bonded in a 1-coordinate geometry to two equivalent Ca(1), two equivalent Mg(5), two equivalent Mg(6), and one Co(1) atom. Both Mg(3)-Mg(5) bond lengths are 3.02 Å. Both Mg(3)-Mg(6) bond lengths are 3.27 Å. The Mg(3)-Co(1) bond length is 2.89 Å. In the fourth Mg site, Mg(4) is bonded to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(4), two equivalent Mg(5), two equivalent Mg(6), and two equivalent Mg(7) atoms to form MgMg12 cuboctahedra that share corners with four equivalent Ca(1)Mg10Co2 cuboctahedra, corners with six equivalent Mg(4)Mg12 cuboctahedra, edges with two equivalent Mg(1)Mg12 cuboctahedra, edges with two equivalent Mg(2)Mg12 cuboctahedra, edges with two equivalent Mg(4)Mg12 cuboctahedra, edges with four equivalent Mg(6)CaMg11 cuboctahedra, faces with two equivalent Mg(6)CaMg11 cuboctahedra, faces with two equivalent Mg(1)Mg12 cuboctahedra, faces with two equivalent Mg(2)Mg12 cuboctahedra, and faces with two equivalent Mg(4)Mg12 cuboctahedra. There is one shorter (3.07 Å) and one longer (3.19 Å) Mg(4)-Mg(4) bond length. Both Mg(4)-Mg(5) bond lengths are 3.16 Å. Both Mg(4)-Mg(6) bond lengths are 3.04 Å. Both Mg(4)-Mg(7) bond lengths are 3.42 Å. In the fifth Mg site, Mg(5) is bonded in a 12-coordinate geometry to one Ca(1), one Mg(1), one Mg(2), one Mg(3), one Mg(4), two equivalent Mg(5), two equivalent Mg(6), two equivalent Mg(7), and one Co(1) atom. There is one shorter (3.02 Å) and one longer (3.23 Å) Mg(5)-Mg(5) bond length. There is one shorter (3.18 Å) and one longer (3.27 Å) Mg(5)-Mg(6) bond length. There is one shorter (3.08 Å) and one longer (3.38 Å) Mg(5)-Mg(7) bond length. The Mg(5)-Co(1) bond length is 3.05 Å. In the sixth Mg site, Mg(6) is bonded to one Ca(1), one Mg(1), two equivalent Mg(3), two equivalent Mg(4), two equivalent Mg(7), and four equivalent Mg(5) atoms to form distorted MgCaMg11 cuboctahedra that share corners with six equivalent Mg(6)CaMg11 cuboctahedra, edges with two equivalent Ca(1)Mg10Co2 cuboctahedra, edges with two equivalent Mg(1)Mg12 cuboctahedra, edges with four equivalent Mg(4)Mg12 cuboctahedra,  a faceface with one Ca(1)Mg10Co2 cuboctahedra,  a faceface with one Mg(1)Mg12 cuboctahedra, faces with two equivalent Mg(6)CaMg11 cuboctahedra, faces with two equivalent Mg(4)Mg12 cuboctahedra, and faces with three equivalent Mg(2)Mg12 cuboctahedra. Both Mg(6)-Mg(7) bond lengths are 3.16 Å. In the seventh Mg site, Mg(7) is bonded in a distorted single-bond geometry to one Mg(2), two equivalent Mg(4), two equivalent Mg(6), four equivalent Mg(5), and one Co(1) atom. The Mg(7)-Co(1) bond length is 2.92 Å. Co(1) is bonded in a 10-coordinate geometry to two equivalent Ca(1), two equivalent Mg(3), two equivalent Mg(7), and four equivalent Mg(5) atoms.