Sm2Mn2O7 crystallizes in the cubic Fd-3m space group. Sm(1) is bonded to two equivalent O(2) and six equivalent O(1) atoms to form distorted SmO8 hexagonal bipyramids that share edges with six equivalent Sm(1)O8 hexagonal bipyramids and edges with six equivalent Mn(1)O6 octahedra. Mn(1) is bonded to six equivalent O(1) atoms to form MnO6 octahedra that share corners with six equivalent Mn(1)O6 octahedra and edges with six equivalent Sm(1)O8 hexagonal bipyramids. The corner-sharing octahedral tilt angles are 46°. There are two inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to two equivalent Sm(1) and two equivalent Mn(1) atoms. In the second O site, O(2) is bonded to four equivalent Sm(1) atoms to form corner-sharing OSm4 tetrahedra.
Sm2Mn2O7 crystallizes in the cubic Fd-3m space group. Sm(1) is bonded to two equivalent O(2) and six equivalent O(1) atoms to form distorted SmO8 hexagonal bipyramids that share edges with six equivalent Sm(1)O8 hexagonal bipyramids and edges with six equivalent Mn(1)O6 octahedra. Both Sm(1)-O(2) bond lengths are 2.18 Å. All Sm(1)-O(1) bond lengths are 2.50 Å. Mn(1) is bonded to six equivalent O(1) atoms to form MnO6 octahedra that share corners with six equivalent Mn(1)O6 octahedra and edges with six equivalent Sm(1)O8 hexagonal bipyramids. The corner-sharing octahedral tilt angles are 46°. All Mn(1)-O(1) bond lengths are 1.93 Å. There are two inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to two equivalent Sm(1) and two equivalent Mn(1) atoms. In the second O site, O(2) is bonded to four equivalent Sm(1) atoms to form corner-sharing OSm4 tetrahedra.