BaMgNd2Mn2O7 crystallizes in the tetragonal I-4m2 space group. Ba(1) is bonded in a 4-coordinate geometry to four equivalent O(4) atoms. Mg(1) is bonded in a square co-planar geometry to four equivalent O(3) atoms. Nd(1) is bonded in a 5-coordinate geometry to one O(3), two equivalent O(1), and two equivalent O(2) atoms. Mn(1) is bonded to one O(4), two equivalent O(1), and two equivalent O(2) atoms to form distorted corner-sharing MnO5 trigonal bipyramids. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to two equivalent Nd(1) and two equivalent Mn(1) atoms. In the second O site, O(2) is bonded to two equivalent Nd(1) and two equivalent Mn(1) atoms to form distorted ONd2Mn2 trigonal pyramids that share corners with two equivalent O(4)Ba4Mn2 octahedra and corners with four equivalent O(2)Nd2Mn2 trigonal pyramids. The corner-sharing octahedral tilt angles are 72°. In the third O site, O(3) is bonded in a T-shaped geometry to two equivalent Mg(1) and one Nd(1) atom. In the fourth O site, O(4) is bonded to four equivalent Ba(1) and two equivalent Mn(1) atoms to form OBa4Mn2 octahedra that share corners with four equivalent O(4)Ba4Mn2 octahedra, corners with four equivalent O(2)Nd2Mn2 trigonal pyramids, and edges with four equivalent O(4)Ba4Mn2 octahedra. The corner-sharing octahedra are not tilted.
BaMgNd2Mn2O7 crystallizes in the tetragonal I-4m2 space group. Ba(1) is bonded in a 4-coordinate geometry to four equivalent O(4) atoms. All Ba(1)-O(4) bond lengths are 2.93 Å. Mg(1) is bonded in a square co-planar geometry to four equivalent O(3) atoms. All Mg(1)-O(3) bond lengths are 2.09 Å. Nd(1) is bonded in a 5-coordinate geometry to one O(3), two equivalent O(1), and two equivalent O(2) atoms. The Nd(1)-O(3) bond length is 2.35 Å. Both Nd(1)-O(1) bond lengths are 2.42 Å. Both Nd(1)-O(2) bond lengths are 2.31 Å. Mn(1) is bonded to one O(4), two equivalent O(1), and two equivalent O(2) atoms to form distorted corner-sharing MnO5 trigonal bipyramids. The Mn(1)-O(4) bond length is 2.10 Å. Both Mn(1)-O(1) bond lengths are 2.12 Å. Both Mn(1)-O(2) bond lengths are 2.18 Å. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to two equivalent Nd(1) and two equivalent Mn(1) atoms. In the second O site, O(2) is bonded to two equivalent Nd(1) and two equivalent Mn(1) atoms to form distorted ONd2Mn2 trigonal pyramids that share corners with two equivalent O(4)Ba4Mn2 octahedra and corners with four equivalent O(2)Nd2Mn2 trigonal pyramids. The corner-sharing octahedral tilt angles are 72°. In the third O site, O(3) is bonded in a T-shaped geometry to two equivalent Mg(1) and one Nd(1) atom. In the fourth O site, O(4) is bonded to four equivalent Ba(1) and two equivalent Mn(1) atoms to form OBa4Mn2 octahedra that share corners with four equivalent O(4)Ba4Mn2 octahedra, corners with four equivalent O(2)Nd2Mn2 trigonal pyramids, and edges with four equivalent O(4)Ba4Mn2 octahedra. The corner-sharing octahedra are not tilted.