Cs2CdP2O7 crystallizes in the orthorhombic Pnma space group. There are two inequivalent Cs sites. In the first Cs site, Cs(1) is bonded in a 8-coordinate geometry to two equivalent O(2), two equivalent O(3), and four equivalent O(4) atoms. In the second Cs site, Cs(2) is bonded in a 7-coordinate geometry to two equivalent O(1), two equivalent O(2), and three equivalent O(5) atoms. Cd(1) is bonded to one O(3), two equivalent O(2), and two equivalent O(4) atoms to form distorted CdO5 trigonal bipyramids that share corners with two equivalent P(1)O4 tetrahedra and corners with three equivalent P(2)O4 tetrahedra. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(5), and two equivalent O(4) atoms to form PO4 tetrahedra that share  a cornercorner with one P(2)O4 tetrahedra and corners with two equivalent Cd(1)O5 trigonal bipyramids. In the second P site, P(2) is bonded to one O(1), one O(3), and two equivalent O(2) atoms to form PO4 tetrahedra that share  a cornercorner with one P(1)O4 tetrahedra and corners with three equivalent Cd(1)O5 trigonal bipyramids. There are five inequivalent O sites. In the first O site, O(3) is bonded in a distorted bent 150 degrees geometry to two equivalent Cs(1), one Cd(1), and one P(2) atom. In the second O site, O(4) is bonded in a 2-coordinate geometry to two equivalent Cs(1), one Cd(1), and one P(1) atom. In the third O site, O(5) is bonded in a distorted single-bond geometry to three equivalent Cs(2) and one P(1) atom. In the fourth O site, O(1) is bonded in a distorted bent 120 degrees geometry to two equivalent Cs(2), one P(1), and one P(2) atom. In the fifth O site, O(2) is bonded in a 2-coordinate geometry to one Cs(1), one Cs(2), one Cd(1), and one P(2) atom.
Cs2CdP2O7 crystallizes in the orthorhombic Pnma space group. There are two inequivalent Cs sites. In the first Cs site, Cs(1) is bonded in a 8-coordinate geometry to two equivalent O(2), two equivalent O(3), and four equivalent O(4) atoms. Both Cs(1)-O(2) bond lengths are 3.32 Å. Both Cs(1)-O(3) bond lengths are 3.37 Å. There are two shorter (3.25 Å) and two longer (3.32 Å) Cs(1)-O(4) bond lengths. In the second Cs site, Cs(2) is bonded in a 7-coordinate geometry to two equivalent O(1), two equivalent O(2), and three equivalent O(5) atoms. Both Cs(2)-O(1) bond lengths are 3.35 Å. Both Cs(2)-O(2) bond lengths are 3.18 Å. There is one shorter (2.97 Å) and two longer (3.46 Å) Cs(2)-O(5) bond lengths. Cd(1) is bonded to one O(3), two equivalent O(2), and two equivalent O(4) atoms to form distorted CdO5 trigonal bipyramids that share corners with two equivalent P(1)O4 tetrahedra and corners with three equivalent P(2)O4 tetrahedra. The Cd(1)-O(3) bond length is 2.20 Å. Both Cd(1)-O(2) bond lengths are 2.26 Å. Both Cd(1)-O(4) bond lengths are 2.27 Å. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(5), and two equivalent O(4) atoms to form PO4 tetrahedra that share  a cornercorner with one P(2)O4 tetrahedra and corners with two equivalent Cd(1)O5 trigonal bipyramids. The P(1)-O(1) bond length is 1.67 Å. The P(1)-O(5) bond length is 1.52 Å. Both P(1)-O(4) bond lengths are 1.54 Å. In the second P site, P(2) is bonded to one O(1), one O(3), and two equivalent O(2) atoms to form PO4 tetrahedra that share  a cornercorner with one P(1)O4 tetrahedra and corners with three equivalent Cd(1)O5 trigonal bipyramids. The P(2)-O(1) bond length is 1.64 Å. The P(2)-O(3) bond length is 1.53 Å. Both P(2)-O(2) bond lengths are 1.54 Å. There are five inequivalent O sites. In the first O site, O(3) is bonded in a distorted bent 150 degrees geometry to two equivalent Cs(1), one Cd(1), and one P(2) atom. In the second O site, O(4) is bonded in a 2-coordinate geometry to two equivalent Cs(1), one Cd(1), and one P(1) atom. In the third O site, O(5) is bonded in a distorted single-bond geometry to three equivalent Cs(2) and one P(1) atom. In the fourth O site, O(1) is bonded in a distorted bent 120 degrees geometry to two equivalent Cs(2), one P(1), and one P(2) atom. In the fifth O site, O(2) is bonded in a 2-coordinate geometry to one Cs(1), one Cs(2), one Cd(1), and one P(2) atom.