Ho2Mn2O7 crystallizes in the cubic Fd-3m space group. Ho(1) is bonded to two equivalent O(1) and six equivalent O(2) atoms to form distorted HoO8 hexagonal bipyramids that share edges with six equivalent Ho(1)O8 hexagonal bipyramids and edges with six equivalent Mn(1)O6 octahedra. Mn(1) is bonded to six equivalent O(2) atoms to form MnO6 octahedra that share corners with six equivalent Mn(1)O6 octahedra and edges with six equivalent Ho(1)O8 hexagonal bipyramids. The corner-sharing octahedral tilt angles are 48°. There are two inequivalent O sites. In the first O site, O(1) is bonded to four equivalent Ho(1) atoms to form OHo4 tetrahedra that share corners with four equivalent O(1)Ho4 tetrahedra, corners with twelve equivalent O(2)Ho2Mn2 tetrahedra, and edges with six equivalent O(2)Ho2Mn2 tetrahedra. In the second O site, O(2) is bonded to two equivalent Ho(1) and two equivalent Mn(1) atoms to form distorted OHo2Mn2 tetrahedra that share corners with two equivalent O(1)Ho4 tetrahedra, corners with twelve equivalent O(2)Ho2Mn2 tetrahedra,  an edgeedge with one O(1)Ho4 tetrahedra, and edges with four equivalent O(2)Ho2Mn2 tetrahedra.
Ho2Mn2O7 crystallizes in the cubic Fd-3m space group. Ho(1) is bonded to two equivalent O(1) and six equivalent O(2) atoms to form distorted HoO8 hexagonal bipyramids that share edges with six equivalent Ho(1)O8 hexagonal bipyramids and edges with six equivalent Mn(1)O6 octahedra. Both Ho(1)-O(1) bond lengths are 2.14 Å. All Ho(1)-O(2) bond lengths are 2.43 Å. Mn(1) is bonded to six equivalent O(2) atoms to form MnO6 octahedra that share corners with six equivalent Mn(1)O6 octahedra and edges with six equivalent Ho(1)O8 hexagonal bipyramids. The corner-sharing octahedral tilt angles are 48°. All Mn(1)-O(2) bond lengths are 1.91 Å. There are two inequivalent O sites. In the first O site, O(1) is bonded to four equivalent Ho(1) atoms to form OHo4 tetrahedra that share corners with four equivalent O(1)Ho4 tetrahedra, corners with twelve equivalent O(2)Ho2Mn2 tetrahedra, and edges with six equivalent O(2)Ho2Mn2 tetrahedra. In the second O site, O(2) is bonded to two equivalent Ho(1) and two equivalent Mn(1) atoms to form distorted OHo2Mn2 tetrahedra that share corners with two equivalent O(1)Ho4 tetrahedra, corners with twelve equivalent O(2)Ho2Mn2 tetrahedra,  an edgeedge with one O(1)Ho4 tetrahedra, and edges with four equivalent O(2)Ho2Mn2 tetrahedra.