Sm2Co12P7 crystallizes in the hexagonal P-6 space group. There are two inequivalent Sm sites. In the first Sm site, Sm(1) is bonded in a 12-coordinate geometry to six equivalent Co(1) and six equivalent P(3) atoms. In the second Sm site, Sm(2) is bonded in a 18-coordinate geometry to three equivalent Co(1), three equivalent Co(3), six equivalent Co(2), and six equivalent P(1) atoms. There are four inequivalent Co sites. In the first Co site, Co(1) is bonded in a 4-coordinate geometry to one Sm(2), two equivalent Sm(1), two equivalent P(1), and two equivalent P(3) atoms. In the second Co site, Co(2) is bonded to two equivalent Sm(2), two equivalent P(1), and two equivalent P(3) atoms to form distorted CoSm2P4 tetrahedra that share corners with two equivalent Co(3)SmP4 tetrahedra, corners with four equivalent Co(2)Sm2P4 tetrahedra, edges with two equivalent Co(2)Sm2P4 tetrahedra, edges with two equivalent Co(3)SmP4 tetrahedra, faces with two equivalent Co(2)Sm2P4 tetrahedra, and faces with two equivalent Co(3)SmP4 tetrahedra. In the third Co site, Co(3) is bonded to one Sm(2), one P(2), one P(3), and two equivalent P(1) atoms to form distorted CoSmP4 tetrahedra that share corners with two equivalent Co(2)Sm2P4 tetrahedra, corners with six equivalent Co(3)SmP4 tetrahedra, edges with two equivalent Co(2)Sm2P4 tetrahedra, and faces with two equivalent Co(2)Sm2P4 tetrahedra. In the fourth Co site, Co(4) is bonded in a 5-coordinate geometry to one P(1), two equivalent P(2), and two equivalent P(3) atoms. There are three inequivalent P sites. In the first P site, P(1) is bonded in a 9-coordinate geometry to two equivalent Sm(2), one Co(4), two equivalent Co(1), two equivalent Co(2), and two equivalent Co(3) atoms. In the second P site, P(2) is bonded in a 9-coordinate geometry to three equivalent Co(3) and six equivalent Co(4) atoms. In the third P site, P(3) is bonded in a 9-coordinate geometry to two equivalent Sm(1), one Co(3), two equivalent Co(1), two equivalent Co(2), and two equivalent Co(4) atoms.
Sm2Co12P7 crystallizes in the hexagonal P-6 space group. There are two inequivalent Sm sites. In the first Sm site, Sm(1) is bonded in a 12-coordinate geometry to six equivalent Co(1) and six equivalent P(3) atoms. All Sm(1)-Co(1) bond lengths are 2.95 Å. All Sm(1)-P(3) bond lengths are 2.87 Å. In the second Sm site, Sm(2) is bonded in a 18-coordinate geometry to three equivalent Co(1), three equivalent Co(3), six equivalent Co(2), and six equivalent P(1) atoms. All Sm(2)-Co(1) bond lengths are 3.20 Å. All Sm(2)-Co(3) bond lengths are 3.11 Å. All Sm(2)-Co(2) bond lengths are 2.98 Å. All Sm(2)-P(1) bond lengths are 2.90 Å. There are four inequivalent Co sites. In the first Co site, Co(1) is bonded in a 4-coordinate geometry to one Sm(2), two equivalent Sm(1), two equivalent P(1), and two equivalent P(3) atoms. Both Co(1)-P(1) bond lengths are 2.30 Å. There is one shorter (2.28 Å) and one longer (2.29 Å) Co(1)-P(3) bond length. In the second Co site, Co(2) is bonded to two equivalent Sm(2), two equivalent P(1), and two equivalent P(3) atoms to form distorted CoSm2P4 tetrahedra that share corners with two equivalent Co(3)SmP4 tetrahedra, corners with four equivalent Co(2)Sm2P4 tetrahedra, edges with two equivalent Co(2)Sm2P4 tetrahedra, edges with two equivalent Co(3)SmP4 tetrahedra, faces with two equivalent Co(2)Sm2P4 tetrahedra, and faces with two equivalent Co(3)SmP4 tetrahedra. There is one shorter (2.29 Å) and one longer (2.35 Å) Co(2)-P(1) bond length. Both Co(2)-P(3) bond lengths are 2.27 Å. In the third Co site, Co(3) is bonded to one Sm(2), one P(2), one P(3), and two equivalent P(1) atoms to form distorted CoSmP4 tetrahedra that share corners with two equivalent Co(2)Sm2P4 tetrahedra, corners with six equivalent Co(3)SmP4 tetrahedra, edges with two equivalent Co(2)Sm2P4 tetrahedra, and faces with two equivalent Co(2)Sm2P4 tetrahedra. The Co(3)-P(2) bond length is 2.13 Å. The Co(3)-P(3) bond length is 2.19 Å. Both Co(3)-P(1) bond lengths are 2.29 Å. In the fourth Co site, Co(4) is bonded in a 5-coordinate geometry to one P(1), two equivalent P(2), and two equivalent P(3) atoms. The Co(4)-P(1) bond length is 2.23 Å. Both Co(4)-P(2) bond lengths are 2.57 Å. Both Co(4)-P(3) bond lengths are 2.45 Å. There are three inequivalent P sites. In the first P site, P(1) is bonded in a 9-coordinate geometry to two equivalent Sm(2), one Co(4), two equivalent Co(1), two equivalent Co(2), and two equivalent Co(3) atoms. In the second P site, P(2) is bonded in a 9-coordinate geometry to three equivalent Co(3) and six equivalent Co(4) atoms. In the third P site, P(3) is bonded in a 9-coordinate geometry to two equivalent Sm(1), one Co(3), two equivalent Co(1), two equivalent Co(2), and two equivalent Co(4) atoms.