Ho2Ti2O7 crystallizes in the cubic Fd-3m space group. Ho(1) is bonded to two equivalent O(2) and six equivalent O(1) atoms to form distorted HoO8 hexagonal bipyramids that share edges with six equivalent Ho(1)O8 hexagonal bipyramids and edges with six equivalent Ti(1)O6 octahedra. Ti(1) is bonded to six equivalent O(1) atoms to form TiO6 octahedra that share corners with six equivalent Ti(1)O6 octahedra and edges with six equivalent Ho(1)O8 hexagonal bipyramids. The corner-sharing octahedral tilt angles are 49°. There are two inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Ho(1) and two equivalent Ti(1) atoms to form distorted OHo2Ti2 tetrahedra that share corners with two equivalent O(2)Ho4 tetrahedra, corners with twelve equivalent O(1)Ho2Ti2 tetrahedra,  an edgeedge with one O(2)Ho4 tetrahedra, and edges with four equivalent O(1)Ho2Ti2 tetrahedra. In the second O site, O(2) is bonded to four equivalent Ho(1) atoms to form OHo4 tetrahedra that share corners with four equivalent O(2)Ho4 tetrahedra, corners with twelve equivalent O(1)Ho2Ti2 tetrahedra, and edges with six equivalent O(1)Ho2Ti2 tetrahedra.
Ho2Ti2O7 crystallizes in the cubic Fd-3m space group. Ho(1) is bonded to two equivalent O(2) and six equivalent O(1) atoms to form distorted HoO8 hexagonal bipyramids that share edges with six equivalent Ho(1)O8 hexagonal bipyramids and edges with six equivalent Ti(1)O6 octahedra. Both Ho(1)-O(2) bond lengths are 2.18 Å. All Ho(1)-O(1) bond lengths are 2.46 Å. Ti(1) is bonded to six equivalent O(1) atoms to form TiO6 octahedra that share corners with six equivalent Ti(1)O6 octahedra and edges with six equivalent Ho(1)O8 hexagonal bipyramids. The corner-sharing octahedral tilt angles are 49°. All Ti(1)-O(1) bond lengths are 1.96 Å. There are two inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Ho(1) and two equivalent Ti(1) atoms to form distorted OHo2Ti2 tetrahedra that share corners with two equivalent O(2)Ho4 tetrahedra, corners with twelve equivalent O(1)Ho2Ti2 tetrahedra,  an edgeedge with one O(2)Ho4 tetrahedra, and edges with four equivalent O(1)Ho2Ti2 tetrahedra. In the second O site, O(2) is bonded to four equivalent Ho(1) atoms to form OHo4 tetrahedra that share corners with four equivalent O(2)Ho4 tetrahedra, corners with twelve equivalent O(1)Ho2Ti2 tetrahedra, and edges with six equivalent O(1)Ho2Ti2 tetrahedra.