CaCdP2O7 crystallizes in the triclinic P-1 space group. Ca(1) is bonded in a 8-coordinate geometry to one O(3), one O(5), one O(6), one O(7), two equivalent O(1), and two equivalent O(4) atoms. Cd(1) is bonded to one O(1), one O(3), one O(6), one O(7), and two equivalent O(5) atoms to form CdO6 octahedra that share corners with three equivalent P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra, and  an edgeedge with one Cd(1)O6 octahedra. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(2), one O(4), and one O(5) atom to form PO4 tetrahedra that share corners with three equivalent Cd(1)O6 octahedra and  a cornercorner with one P(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 51-62°. In the second P site, P(2) is bonded to one O(2), one O(3), one O(6), and one O(7) 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 52-61°. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a 1-coordinate geometry to two equivalent Ca(1), one Cd(1), and one P(1) atom. In the second O site, O(2) is bonded in a bent 120 degrees geometry to one P(1) and one P(2) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Ca(1), one Cd(1), and one P(2) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to two equivalent Ca(1) and one P(1) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Ca(1), two equivalent Cd(1), and one P(1) atom. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Ca(1), one Cd(1), and one P(2) atom. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one Ca(1), one Cd(1), and one P(2) atom.
CaCdP2O7 crystallizes in the triclinic P-1 space group. Ca(1) is bonded in a 8-coordinate geometry to one O(3), one O(5), one O(6), one O(7), two equivalent O(1), and two equivalent O(4) atoms. The Ca(1)-O(3) bond length is 2.38 Å. The Ca(1)-O(5) bond length is 2.74 Å. The Ca(1)-O(6) bond length is 2.50 Å. The Ca(1)-O(7) bond length is 2.58 Å. There is one shorter (2.51 Å) and one longer (3.08 Å) Ca(1)-O(1) bond length. There is one shorter (2.39 Å) and one longer (2.45 Å) Ca(1)-O(4) bond length. Cd(1) is bonded to one O(1), one O(3), one O(6), one O(7), and two equivalent O(5) atoms to form CdO6 octahedra that share corners with three equivalent P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra, and  an edgeedge with one Cd(1)O6 octahedra. The Cd(1)-O(1) bond length is 2.34 Å. The Cd(1)-O(3) bond length is 2.32 Å. The Cd(1)-O(6) bond length is 2.31 Å. The Cd(1)-O(7) bond length is 2.35 Å. There is one shorter (2.37 Å) and one longer (2.38 Å) Cd(1)-O(5) bond length. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(2), one O(4), and one O(5) atom to form PO4 tetrahedra that share corners with three equivalent Cd(1)O6 octahedra and  a cornercorner with one P(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 51-62°. The P(1)-O(1) bond length is 1.54 Å. The P(1)-O(2) bond length is 1.61 Å. The P(1)-O(4) bond length is 1.52 Å. The P(1)-O(5) bond length is 1.56 Å. In the second P site, P(2) is bonded to one O(2), one O(3), one O(6), and one O(7) 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 52-61°. The P(2)-O(2) bond length is 1.64 Å. The P(2)-O(3) bond length is 1.54 Å. The P(2)-O(6) bond length is 1.52 Å. The P(2)-O(7) bond length is 1.53 Å. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a 1-coordinate geometry to two equivalent Ca(1), one Cd(1), and one P(1) atom. In the second O site, O(2) is bonded in a bent 120 degrees geometry to one P(1) and one P(2) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Ca(1), one Cd(1), and one P(2) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to two equivalent Ca(1) and one P(1) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Ca(1), two equivalent Cd(1), and one P(1) atom. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Ca(1), one Cd(1), and one P(2) atom. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one Ca(1), one Cd(1), and one P(2) atom.