BaMgYMnCuO5 crystallizes in the monoclinic Pm space group. Ba(1) is bonded in a 4-coordinate geometry to two equivalent O(4) and two equivalent O(5) atoms. Mg(1) is bonded in a T-shaped geometry to one O(1) and two equivalent O(5) atoms. Y(1) is bonded in a 7-coordinate geometry to one O(4), two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms. Mn(1) is bonded to one O(5), two equivalent O(1), and two equivalent O(2) atoms to form corner-sharing MnO5 trigonal bipyramids. Cu(1) is bonded in a distorted rectangular see-saw-like geometry to two equivalent O(3) and two equivalent O(4) atoms. There are five inequivalent O sites. In the first O site, O(1) is bonded to one Mg(1), two equivalent Y(1), and two equivalent Mn(1) atoms to form distorted OY2MgMn2 trigonal bipyramids that share corners with two equivalent O(4)Ba2YCu2 square pyramids, corners with four equivalent O(1)Y2MgMn2 trigonal bipyramids, edges with two equivalent O(5)Ba2Mg2Mn square pyramids, and edges with four equivalent O(2)Y2Mn2 trigonal pyramids. In the second O site, O(2) is bonded to two equivalent Y(1) and two equivalent Mn(1) atoms to form distorted OY2Mn2 trigonal pyramids that share corners with two equivalent O(5)Ba2Mg2Mn square pyramids, corners with two equivalent O(4)Ba2YCu2 square pyramids, corners with four equivalent O(2)Y2Mn2 trigonal pyramids, and edges with four equivalent O(1)Y2MgMn2 trigonal bipyramids. In the third O site, O(3) is bonded in a 4-coordinate geometry to two equivalent Y(1) and two equivalent Cu(1) atoms. In the fourth O site, O(4) is bonded to two equivalent Ba(1), one Y(1), and two equivalent Cu(1) atoms to form distorted OBa2YCu2 square pyramids that share corners with four equivalent O(5)Ba2Mg2Mn square pyramids, corners with four equivalent O(4)Ba2YCu2 square pyramids, corners with two equivalent O(1)Y2MgMn2 trigonal bipyramids, and corners with two equivalent O(2)Y2Mn2 trigonal pyramids. In the fifth O site, O(5) is bonded to two equivalent Ba(1), two equivalent Mg(1), and one Mn(1) atom to form distorted OBa2Mg2Mn square pyramids that share corners with four equivalent O(5)Ba2Mg2Mn square pyramids, corners with four equivalent O(4)Ba2YCu2 square pyramids, corners with two equivalent O(2)Y2Mn2 trigonal pyramids, and edges with two equivalent O(1)Y2MgMn2 trigonal bipyramids.
BaMgYMnCuO5 crystallizes in the monoclinic Pm space group. Ba(1) is bonded in a 4-coordinate geometry to two equivalent O(4) and two equivalent O(5) atoms. There is one shorter (2.51 Å) and one longer (2.61 Å) Ba(1)-O(4) bond length. Both Ba(1)-O(5) bond lengths are 2.83 Å. Mg(1) is bonded in a T-shaped geometry to one O(1) and two equivalent O(5) atoms. The Mg(1)-O(1) bond length is 1.95 Å. Both Mg(1)-O(5) bond lengths are 2.08 Å. Y(1) is bonded in a 7-coordinate geometry to one O(4), two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms. The Y(1)-O(4) bond length is 2.51 Å. Both Y(1)-O(1) bond lengths are 2.62 Å. There is one shorter (2.27 Å) and one longer (2.28 Å) Y(1)-O(2) bond length. Both Y(1)-O(3) bond lengths are 2.29 Å. Mn(1) is bonded to one O(5), two equivalent O(1), and two equivalent O(2) atoms to form corner-sharing MnO5 trigonal bipyramids. The Mn(1)-O(5) bond length is 2.35 Å. Both Mn(1)-O(1) bond lengths are 2.05 Å. Both Mn(1)-O(2) bond lengths are 2.08 Å. Cu(1) is bonded in a distorted rectangular see-saw-like geometry to two equivalent O(3) and two equivalent O(4) atoms. There is one shorter (2.14 Å) and one longer (2.19 Å) Cu(1)-O(3) bond length. Both Cu(1)-O(4) bond lengths are 1.97 Å. There are five inequivalent O sites. In the first O site, O(1) is bonded to one Mg(1), two equivalent Y(1), and two equivalent Mn(1) atoms to form distorted OY2MgMn2 trigonal bipyramids that share corners with two equivalent O(4)Ba2YCu2 square pyramids, corners with four equivalent O(1)Y2MgMn2 trigonal bipyramids, edges with two equivalent O(5)Ba2Mg2Mn square pyramids, and edges with four equivalent O(2)Y2Mn2 trigonal pyramids. In the second O site, O(2) is bonded to two equivalent Y(1) and two equivalent Mn(1) atoms to form distorted OY2Mn2 trigonal pyramids that share corners with two equivalent O(5)Ba2Mg2Mn square pyramids, corners with two equivalent O(4)Ba2YCu2 square pyramids, corners with four equivalent O(2)Y2Mn2 trigonal pyramids, and edges with four equivalent O(1)Y2MgMn2 trigonal bipyramids. In the third O site, O(3) is bonded in a 4-coordinate geometry to two equivalent Y(1) and two equivalent Cu(1) atoms. In the fourth O site, O(4) is bonded to two equivalent Ba(1), one Y(1), and two equivalent Cu(1) atoms to form distorted OBa2YCu2 square pyramids that share corners with four equivalent O(5)Ba2Mg2Mn square pyramids, corners with four equivalent O(4)Ba2YCu2 square pyramids, corners with two equivalent O(1)Y2MgMn2 trigonal bipyramids, and corners with two equivalent O(2)Y2Mn2 trigonal pyramids. In the fifth O site, O(5) is bonded to two equivalent Ba(1), two equivalent Mg(1), and one Mn(1) atom to form distorted OBa2Mg2Mn square pyramids that share corners with four equivalent O(5)Ba2Mg2Mn square pyramids, corners with four equivalent O(4)Ba2YCu2 square pyramids, corners with two equivalent O(2)Y2Mn2 trigonal pyramids, and edges with two equivalent O(1)Y2MgMn2 trigonal bipyramids.