Y2Ge2O7 crystallizes in the cubic Fd-3m space group. Y(1) is bonded to two equivalent O(2) and six equivalent O(1) atoms to form distorted YO8 hexagonal bipyramids that share edges with six equivalent Y(1)O8 hexagonal bipyramids and edges with six equivalent Ge(1)O6 octahedra. Ge(1) is bonded to six equivalent O(1) atoms to form GeO6 octahedra that share corners with six equivalent Ge(1)O6 octahedra and edges with six equivalent Y(1)O8 hexagonal bipyramids. The corner-sharing octahedral tilt angles are 47°. There are two inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Y(1) and two equivalent Ge(1) atoms to form distorted OY2Ge2 tetrahedra that share corners with two equivalent O(2)Y4 tetrahedra, corners with twelve equivalent O(1)Y2Ge2 tetrahedra,  an edgeedge with one O(2)Y4 tetrahedra, and edges with four equivalent O(1)Y2Ge2 tetrahedra. In the second O site, O(2) is bonded to four equivalent Y(1) atoms to form OY4 tetrahedra that share corners with four equivalent O(2)Y4 tetrahedra, corners with twelve equivalent O(1)Y2Ge2 tetrahedra, and edges with six equivalent O(1)Y2Ge2 tetrahedra.
Y2Ge2O7 crystallizes in the cubic Fd-3m space group. Y(1) is bonded to two equivalent O(2) and six equivalent O(1) atoms to form distorted YO8 hexagonal bipyramids that share edges with six equivalent Y(1)O8 hexagonal bipyramids and edges with six equivalent Ge(1)O6 octahedra. Both Y(1)-O(2) bond lengths are 2.15 Å. All Y(1)-O(1) bond lengths are 2.46 Å. Ge(1) is bonded to six equivalent O(1) atoms to form GeO6 octahedra that share corners with six equivalent Ge(1)O6 octahedra and edges with six equivalent Y(1)O8 hexagonal bipyramids. The corner-sharing octahedral tilt angles are 47°. All Ge(1)-O(1) bond lengths are 1.91 Å. There are two inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Y(1) and two equivalent Ge(1) atoms to form distorted OY2Ge2 tetrahedra that share corners with two equivalent O(2)Y4 tetrahedra, corners with twelve equivalent O(1)Y2Ge2 tetrahedra,  an edgeedge with one O(2)Y4 tetrahedra, and edges with four equivalent O(1)Y2Ge2 tetrahedra. In the second O site, O(2) is bonded to four equivalent Y(1) atoms to form OY4 tetrahedra that share corners with four equivalent O(2)Y4 tetrahedra, corners with twelve equivalent O(1)Y2Ge2 tetrahedra, and edges with six equivalent O(1)Y2Ge2 tetrahedra.