Ce3Cu4(P2O)2 crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Ce sites. In the first Ce site, Ce(1) is bonded in a 4-coordinate geometry to four equivalent P(2) and four equivalent O(1) atoms. In the second Ce site, Ce(2) is bonded in a 16-coordinate geometry to eight equivalent Cu(1) and eight equivalent P(1) atoms. Cu(1) is bonded to two equivalent Ce(2), two equivalent P(1), and two equivalent P(2) atoms to form a mixture of face, corner, and edge-sharing CuCe2P4 tetrahedra. There are two inequivalent P sites. In the first P site, P(1) is bonded in a 9-coordinate geometry to four equivalent Ce(2), four equivalent Cu(1), and one P(1) atom. In the second P site, P(2) is bonded in a 8-coordinate geometry to four equivalent Ce(1) and four equivalent Cu(1) atoms. O(1) is bonded to four equivalent Ce(1) atoms to form a mixture of corner and edge-sharing OCe4 tetrahedra.
Ce3Cu4(P2O)2 crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Ce sites. In the first Ce site, Ce(1) is bonded in a 4-coordinate geometry to four equivalent P(2) and four equivalent O(1) atoms. All Ce(1)-P(2) bond lengths are 3.12 Å. All Ce(1)-O(1) bond lengths are 2.33 Å. In the second Ce site, Ce(2) is bonded in a 16-coordinate geometry to eight equivalent Cu(1) and eight equivalent P(1) atoms. All Ce(2)-Cu(1) bond lengths are 3.27 Å. All Ce(2)-P(1) bond lengths are 3.00 Å. Cu(1) is bonded to two equivalent Ce(2), two equivalent P(1), and two equivalent P(2) atoms to form a mixture of face, corner, and edge-sharing CuCe2P4 tetrahedra. Both Cu(1)-P(1) bond lengths are 2.41 Å. Both Cu(1)-P(2) bond lengths are 2.35 Å. There are two inequivalent P sites. In the first P site, P(1) is bonded in a 9-coordinate geometry to four equivalent Ce(2), four equivalent Cu(1), and one P(1) atom. The P(1)-P(1) bond length is 2.41 Å. In the second P site, P(2) is bonded in a 8-coordinate geometry to four equivalent Ce(1) and four equivalent Cu(1) atoms. O(1) is bonded to four equivalent Ce(1) atoms to form a mixture of corner and edge-sharing OCe4 tetrahedra.