Ba2MgNd4(CuO5)2 crystallizes in the monoclinic Pm space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 12-coordinate geometry to one Mg(1), one Cu(1), two equivalent Cu(2), two equivalent O(1), two equivalent O(2), two equivalent O(3), and two equivalent O(6) atoms. In the second Ba site, Ba(2) is bonded in a 6-coordinate geometry to two equivalent O(1), two equivalent O(3), two equivalent O(4), and two equivalent O(5) atoms. Mg(1) is bonded in a distorted square co-planar geometry to one Ba(1), two equivalent O(2), and two equivalent O(4) atoms. There are four inequivalent Nd sites. In the first Nd site, Nd(1) is bonded in a 5-coordinate geometry to one O(5), one O(6), two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms. In the second Nd site, Nd(2) is bonded in a 7-coordinate geometry to one O(5), two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms. In the third Nd site, Nd(3) is bonded in a 6-coordinate geometry to one O(5), one O(6), two equivalent O(1), and two equivalent O(3) atoms. In the fourth Nd site, Nd(4) is bonded in a 6-coordinate geometry to one O(5), one O(6), two equivalent O(2), and two equivalent O(4) atoms. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a 4-coordinate geometry to one Ba(1), two equivalent O(1), and two equivalent O(2) atoms. In the second Cu site, Cu(2) is bonded in a square co-planar geometry to two equivalent Ba(1), two equivalent O(3), and two equivalent O(4) atoms. There are six inequivalent O sites. In the first O site, O(1) is bonded in a 6-coordinate geometry to one Ba(1), one Ba(2), one Nd(1), one Nd(2), one Nd(3), and one Cu(1) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Ba(1), one Mg(1), one Nd(2), one Nd(4), and one Cu(1) atom. In the third O site, O(3) is bonded to one Ba(1), one Ba(2), one Nd(1), one Nd(3), and one Cu(2) atom to form a mixture of distorted edge and face-sharing OBa2Nd2Cu square pyramids. In the fourth O site, O(4) is bonded in a 6-coordinate geometry to one Ba(2), one Mg(1), one Nd(1), one Nd(2), one Nd(4), and one Cu(2) atom. In the fifth O site, O(5) is bonded in a 6-coordinate geometry to two equivalent Ba(2), one Nd(1), one Nd(2), one Nd(3), and one Nd(4) atom. In the sixth O site, O(6) is bonded in a 5-coordinate geometry to two equivalent Ba(1), one Nd(1), one Nd(3), and one Nd(4) atom.
Ba2MgNd4(CuO5)2 crystallizes in the monoclinic Pm space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 12-coordinate geometry to one Mg(1), one Cu(1), two equivalent Cu(2), two equivalent O(1), two equivalent O(2), two equivalent O(3), and two equivalent O(6) atoms. The Ba(1)-Mg(1) bond length is 2.93 Å. The Ba(1)-Cu(1) bond length is 2.97 Å. There is one shorter (2.99 Å) and one longer (3.59 Å) Ba(1)-Cu(2) bond length. Both Ba(1)-O(1) bond lengths are 2.83 Å. Both Ba(1)-O(2) bond lengths are 3.34 Å. Both Ba(1)-O(3) bond lengths are 2.68 Å. Both Ba(1)-O(6) bond lengths are 3.03 Å. In the second Ba site, Ba(2) is bonded in a 6-coordinate geometry to two equivalent O(1), two equivalent O(3), two equivalent O(4), and two equivalent O(5) atoms. Both Ba(2)-O(1) bond lengths are 2.95 Å. Both Ba(2)-O(3) bond lengths are 2.75 Å. Both Ba(2)-O(4) bond lengths are 3.30 Å. Both Ba(2)-O(5) bond lengths are 3.03 Å. Mg(1) is bonded in a distorted square co-planar geometry to one Ba(1), two equivalent O(2), and two equivalent O(4) atoms. Both Mg(1)-O(2) bond lengths are 2.11 Å. Both Mg(1)-O(4) bond lengths are 2.04 Å. There are four inequivalent Nd sites. In the first Nd site, Nd(1) is bonded in a 5-coordinate geometry to one O(5), one O(6), two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms. The Nd(1)-O(5) bond length is 3.04 Å. The Nd(1)-O(6) bond length is 2.32 Å. Both Nd(1)-O(1) bond lengths are 2.42 Å. Both Nd(1)-O(3) bond lengths are 2.46 Å. Both Nd(1)-O(4) bond lengths are 3.00 Å. In the second Nd site, Nd(2) is bonded in a 7-coordinate geometry to one O(5), two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms. The Nd(2)-O(5) bond length is 2.40 Å. Both Nd(2)-O(1) bond lengths are 2.62 Å. Both Nd(2)-O(2) bond lengths are 2.45 Å. Both Nd(2)-O(4) bond lengths are 2.35 Å. In the third Nd site, Nd(3) is bonded in a 6-coordinate geometry to one O(5), one O(6), two equivalent O(1), and two equivalent O(3) atoms. The Nd(3)-O(5) bond length is 2.39 Å. The Nd(3)-O(6) bond length is 2.48 Å. Both Nd(3)-O(1) bond lengths are 2.53 Å. Both Nd(3)-O(3) bond lengths are 2.30 Å. In the fourth Nd site, Nd(4) is bonded in a 6-coordinate geometry to one O(5), one O(6), two equivalent O(2), and two equivalent O(4) atoms. The Nd(4)-O(5) bond length is 2.45 Å. The Nd(4)-O(6) bond length is 2.34 Å. Both Nd(4)-O(2) bond lengths are 2.37 Å. Both Nd(4)-O(4) bond lengths are 2.68 Å. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a 4-coordinate geometry to one Ba(1), two equivalent O(1), and two equivalent O(2) atoms. Both Cu(1)-O(1) bond lengths are 2.01 Å. Both Cu(1)-O(2) bond lengths are 2.28 Å. In the second Cu site, Cu(2) is bonded in a square co-planar geometry to two equivalent Ba(1), two equivalent O(3), and two equivalent O(4) atoms. Both Cu(2)-O(3) bond lengths are 2.10 Å. Both Cu(2)-O(4) bond lengths are 2.10 Å. There are six inequivalent O sites. In the first O site, O(1) is bonded in a 6-coordinate geometry to one Ba(1), one Ba(2), one Nd(1), one Nd(2), one Nd(3), and one Cu(1) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Ba(1), one Mg(1), one Nd(2), one Nd(4), and one Cu(1) atom. In the third O site, O(3) is bonded to one Ba(1), one Ba(2), one Nd(1), one Nd(3), and one Cu(2) atom to form a mixture of distorted edge and face-sharing OBa2Nd2Cu square pyramids. In the fourth O site, O(4) is bonded in a 6-coordinate geometry to one Ba(2), one Mg(1), one Nd(1), one Nd(2), one Nd(4), and one Cu(2) atom. In the fifth O site, O(5) is bonded in a 6-coordinate geometry to two equivalent Ba(2), one Nd(1), one Nd(2), one Nd(3), and one Nd(4) atom. In the sixth O site, O(6) is bonded in a 5-coordinate geometry to two equivalent Ba(1), one Nd(1), one Nd(3), and one Nd(4) atom.