CdCuP2O7 crystallizes in the monoclinic C2 space group. Cu(1) is bonded in a 6-coordinate geometry to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms. Cd(1) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form distorted CdO6 octahedra that share corners with six equivalent P(1)O4 tetrahedra. P(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form PO4 tetrahedra that share corners with three equivalent Cd(1)O6 octahedra and  a cornercorner with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 45-63°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Cu(1), one Cd(1), and one P(1) atom. In the second O site, O(2) is bonded in a linear geometry to two equivalent P(1) atoms. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Cu(1), one Cd(1), and one P(1) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Cu(1), one Cd(1), and one P(1) atom.
CdCuP2O7 crystallizes in the monoclinic C2 space group. Cu(1) is bonded in a 6-coordinate geometry to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms. Both Cu(1)-O(1) bond lengths are 2.53 Å. Both Cu(1)-O(3) bond lengths are 2.05 Å. Both Cu(1)-O(4) bond lengths are 2.10 Å. Cd(1) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form distorted CdO6 octahedra that share corners with six equivalent P(1)O4 tetrahedra. Both Cd(1)-O(1) bond lengths are 2.16 Å. Both Cd(1)-O(3) bond lengths are 2.58 Å. Both Cd(1)-O(4) bond lengths are 2.21 Å. P(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form PO4 tetrahedra that share corners with three equivalent Cd(1)O6 octahedra and  a cornercorner with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 45-63°. The P(1)-O(1) bond length is 1.51 Å. The P(1)-O(2) bond length is 1.59 Å. The P(1)-O(3) bond length is 1.55 Å. The P(1)-O(4) bond length is 1.55 Å. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Cu(1), one Cd(1), and one P(1) atom. In the second O site, O(2) is bonded in a linear geometry to two equivalent P(1) atoms. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Cu(1), one Cd(1), and one P(1) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Cu(1), one Cd(1), and one P(1) atom.