Eu2MnSbO7 crystallizes in the orthorhombic Imma space group. There are two inequivalent Eu sites. In the first Eu site, Eu(1) is bonded to two equivalent O(1), two equivalent O(4), and four equivalent O(3) atoms to form distorted EuO8 hexagonal bipyramids that share edges with two equivalent Eu(1)O8 hexagonal bipyramids, edges with four equivalent Eu(2)O8 hexagonal bipyramids, edges with two equivalent Mn(1)O6 octahedra, and edges with four equivalent Sb(1)O6 octahedra. In the second Eu site, Eu(2) is bonded to two equivalent O(2), two equivalent O(4), and four equivalent O(3) atoms to form distorted EuO8 hexagonal bipyramids that share edges with two equivalent Eu(2)O8 hexagonal bipyramids, edges with four equivalent Eu(1)O8 hexagonal bipyramids, edges with two equivalent Sb(1)O6 octahedra, and edges with four equivalent Mn(1)O6 octahedra. Mn(1) is bonded to two equivalent O(2) and four equivalent O(3) atoms to form MnO6 octahedra that share corners with two equivalent Mn(1)O6 octahedra, corners with four equivalent Sb(1)O6 octahedra, edges with two equivalent Eu(1)O8 hexagonal bipyramids, and edges with four equivalent Eu(2)O8 hexagonal bipyramids. The corner-sharing octahedral tilt angles are 46°. Sb(1) is bonded to two equivalent O(1) and four equivalent O(3) atoms to form SbO6 octahedra that share corners with two equivalent Sb(1)O6 octahedra, corners with four equivalent Mn(1)O6 octahedra, edges with two equivalent Eu(2)O8 hexagonal bipyramids, and edges with four equivalent Eu(1)O8 hexagonal bipyramids. The corner-sharing octahedral tilt angles range from 46-47°. There are four inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Eu(1) and two equivalent Sb(1) atoms to form distorted OEu2Sb2 tetrahedra that share corners with two equivalent O(4)Eu4 tetrahedra, corners with four equivalent O(1)Eu2Sb2 tetrahedra, and  an edgeedge with one O(4)Eu4 tetrahedra. In the second O site, O(2) is bonded in a 4-coordinate geometry to two equivalent Eu(2) and two equivalent Mn(1) atoms. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Eu(1), one Eu(2), one Mn(1), and one Sb(1) atom. In the fourth O site, O(4) is bonded to two equivalent Eu(1) and two equivalent Eu(2) atoms to form OEu4 tetrahedra that share corners with two equivalent O(1)Eu2Sb2 tetrahedra, corners with four equivalent O(4)Eu4 tetrahedra, and  an edgeedge with one O(1)Eu2Sb2 tetrahedra.
Eu2MnSbO7 crystallizes in the orthorhombic Imma space group. There are two inequivalent Eu sites. In the first Eu site, Eu(1) is bonded to two equivalent O(1), two equivalent O(4), and four equivalent O(3) atoms to form distorted EuO8 hexagonal bipyramids that share edges with two equivalent Eu(1)O8 hexagonal bipyramids, edges with four equivalent Eu(2)O8 hexagonal bipyramids, edges with two equivalent Mn(1)O6 octahedra, and edges with four equivalent Sb(1)O6 octahedra. Both Eu(1)-O(1) bond lengths are 2.57 Å. Both Eu(1)-O(4) bond lengths are 2.25 Å. All Eu(1)-O(3) bond lengths are 2.59 Å. In the second Eu site, Eu(2) is bonded to two equivalent O(2), two equivalent O(4), and four equivalent O(3) atoms to form distorted EuO8 hexagonal bipyramids that share edges with two equivalent Eu(2)O8 hexagonal bipyramids, edges with four equivalent Eu(1)O8 hexagonal bipyramids, edges with two equivalent Sb(1)O6 octahedra, and edges with four equivalent Mn(1)O6 octahedra. Both Eu(2)-O(2) bond lengths are 2.60 Å. Both Eu(2)-O(4) bond lengths are 2.26 Å. All Eu(2)-O(3) bond lengths are 2.59 Å. Mn(1) is bonded to two equivalent O(2) and four equivalent O(3) atoms to form MnO6 octahedra that share corners with two equivalent Mn(1)O6 octahedra, corners with four equivalent Sb(1)O6 octahedra, edges with two equivalent Eu(1)O8 hexagonal bipyramids, and edges with four equivalent Eu(2)O8 hexagonal bipyramids. The corner-sharing octahedral tilt angles are 46°. Both Mn(1)-O(2) bond lengths are 2.00 Å. All Mn(1)-O(3) bond lengths are 2.00 Å. Sb(1) is bonded to two equivalent O(1) and four equivalent O(3) atoms to form SbO6 octahedra that share corners with two equivalent Sb(1)O6 octahedra, corners with four equivalent Mn(1)O6 octahedra, edges with two equivalent Eu(2)O8 hexagonal bipyramids, and edges with four equivalent Eu(1)O8 hexagonal bipyramids. The corner-sharing octahedral tilt angles range from 46-47°. Both Sb(1)-O(1) bond lengths are 2.02 Å. All Sb(1)-O(3) bond lengths are 2.01 Å. There are four inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Eu(1) and two equivalent Sb(1) atoms to form distorted OEu2Sb2 tetrahedra that share corners with two equivalent O(4)Eu4 tetrahedra, corners with four equivalent O(1)Eu2Sb2 tetrahedra, and  an edgeedge with one O(4)Eu4 tetrahedra. In the second O site, O(2) is bonded in a 4-coordinate geometry to two equivalent Eu(2) and two equivalent Mn(1) atoms. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Eu(1), one Eu(2), one Mn(1), and one Sb(1) atom. In the fourth O site, O(4) is bonded to two equivalent Eu(1) and two equivalent Eu(2) atoms to form OEu4 tetrahedra that share corners with two equivalent O(1)Eu2Sb2 tetrahedra, corners with four equivalent O(4)Eu4 tetrahedra, and  an edgeedge with one O(1)Eu2Sb2 tetrahedra.