Ba2Mn2O5 crystallizes in the orthorhombic Ima2 space group. Ba(1) is bonded in a 10-coordinate geometry to two equivalent O(3), four equivalent O(1), and four equivalent O(2) atoms. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form MnO6 octahedra that share corners with four equivalent Mn(1)O6 octahedra and corners with two equivalent Mn(2)O4 tetrahedra. The corner-sharing octahedral tilt angles are 4°. In the second Mn site, Mn(2) is bonded to two equivalent O(2) and two equivalent O(3) atoms to form distorted MnO4 tetrahedra that share corners with two equivalent Mn(1)O6 octahedra and corners with two equivalent Mn(2)O4 tetrahedra. The corner-sharing octahedral tilt angles are 22°. There are three inequivalent O sites. In the first O site, O(1) is bonded to four equivalent Ba(1) and two equivalent Mn(1) atoms to form a mixture of distorted corner, edge, and face-sharing OBa4Mn2 octahedra. The corner-sharing octahedral tilt angles are 1°. In the second O site, O(2) is bonded in a 6-coordinate geometry to four equivalent Ba(1), one Mn(1), and one Mn(2) atom. In the third O site, O(3) is bonded in a 2-coordinate geometry to four equivalent Ba(1) and two equivalent Mn(2) atoms.
Ba2Mn2O5 crystallizes in the orthorhombic Ima2 space group. Ba(1) is bonded in a 10-coordinate geometry to two equivalent O(3), four equivalent O(1), and four equivalent O(2) atoms. There is one shorter (2.78 Å) and one longer (3.36 Å) Ba(1)-O(3) bond length. There are a spread of Ba(1)-O(1) bond distances ranging from 2.73-2.85 Å. There are a spread of Ba(1)-O(2) bond distances ranging from 2.73-3.15 Å. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form MnO6 octahedra that share corners with four equivalent Mn(1)O6 octahedra and corners with two equivalent Mn(2)O4 tetrahedra. The corner-sharing octahedral tilt angles are 4°. Both Mn(1)-O(2) bond lengths are 2.36 Å. All Mn(1)-O(1) bond lengths are 2.06 Å. In the second Mn site, Mn(2) is bonded to two equivalent O(2) and two equivalent O(3) atoms to form distorted MnO4 tetrahedra that share corners with two equivalent Mn(1)O6 octahedra and corners with two equivalent Mn(2)O4 tetrahedra. The corner-sharing octahedral tilt angles are 22°. Both Mn(2)-O(2) bond lengths are 1.88 Å. There is one shorter (1.88 Å) and one longer (1.93 Å) Mn(2)-O(3) bond length. There are three inequivalent O sites. In the first O site, O(1) is bonded to four equivalent Ba(1) and two equivalent Mn(1) atoms to form a mixture of distorted corner, edge, and face-sharing OBa4Mn2 octahedra. The corner-sharing octahedral tilt angles are 1°. In the second O site, O(2) is bonded in a 6-coordinate geometry to four equivalent Ba(1), one Mn(1), and one Mn(2) atom. In the third O site, O(3) is bonded in a 2-coordinate geometry to four equivalent Ba(1) and two equivalent Mn(2) atoms.