Cd2Nb2O7 crystallizes in the cubic Fd-3m space group. Nb(1) is bonded to six equivalent O(2) atoms to form NbO6 octahedra that share corners with six equivalent Nb(1)O6 octahedra and edges with six equivalent Cd(1)O8 hexagonal bipyramids. The corner-sharing octahedral tilt angles are 43°. Cd(1) is bonded to two equivalent O(1) and six equivalent O(2) atoms to form distorted CdO8 hexagonal bipyramids that share edges with six equivalent Cd(1)O8 hexagonal bipyramids and edges with six equivalent Nb(1)O6 octahedra. There are two inequivalent O sites. In the first O site, O(1) is bonded to four equivalent Cd(1) atoms to form corner-sharing OCd4 tetrahedra. In the second O site, O(2) is bonded in a 4-coordinate geometry to two equivalent Nb(1) and two equivalent Cd(1) atoms.
Cd2Nb2O7 crystallizes in the cubic Fd-3m space group. Nb(1) is bonded to six equivalent O(2) atoms to form NbO6 octahedra that share corners with six equivalent Nb(1)O6 octahedra and edges with six equivalent Cd(1)O8 hexagonal bipyramids. The corner-sharing octahedral tilt angles are 43°. All Nb(1)-O(2) bond lengths are 1.99 Å. Cd(1) is bonded to two equivalent O(1) and six equivalent O(2) atoms to form distorted CdO8 hexagonal bipyramids that share edges with six equivalent Cd(1)O8 hexagonal bipyramids and edges with six equivalent Nb(1)O6 octahedra. Both Cd(1)-O(1) bond lengths are 2.27 Å. All Cd(1)-O(2) bond lengths are 2.64 Å. There are two inequivalent O sites. In the first O site, O(1) is bonded to four equivalent Cd(1) atoms to form corner-sharing OCd4 tetrahedra. In the second O site, O(2) is bonded in a 4-coordinate geometry to two equivalent Nb(1) and two equivalent Cd(1) atoms.