Ba4Nd2NiCu6O15 crystallizes in the orthorhombic Imm2 space group. There are four inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 10-coordinate geometry to two equivalent O(1), two equivalent O(11), two equivalent O(15), and four equivalent O(3) atoms. In the second Ba site, Ba(2) is bonded in a distorted q6 geometry to two equivalent O(12), two equivalent O(15), two equivalent O(2), and four equivalent O(4) atoms. In the third Ba site, Ba(3) is bonded in a 8-coordinate geometry to two equivalent O(13), two equivalent O(9), and four equivalent O(7) atoms. In the fourth Ba site, Ba(4) is bonded in a 8-coordinate geometry to two equivalent O(10), two equivalent O(14), and four equivalent O(8) atoms. There are two inequivalent Nd sites. In the first Nd site, Nd(1) is bonded in a body-centered cubic geometry to two equivalent O(1), two equivalent O(11), two equivalent O(13), and two equivalent O(9) atoms. In the second Nd site, Nd(2) is bonded in a body-centered cubic geometry to two equivalent O(10), two equivalent O(12), two equivalent O(14), and two equivalent O(2) atoms. Ni(1) is bonded to one O(8), two equivalent O(10), and two equivalent O(14) atoms to form NiO5 square pyramids that share corners with four equivalent Ni(1)O5 square pyramids and  a cornercorner with one Cu(2)O5 trigonal bipyramid. There are six inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one O(7), two equivalent O(5), and two equivalent O(6) atoms to form a mixture of distorted corner and edge-sharing CuO5 trigonal bipyramids. In the second Cu site, Cu(2) is bonded to one O(8), two equivalent O(5), and two equivalent O(6) atoms to form distorted CuO5 trigonal bipyramids that share  a cornercorner with one Ni(1)O5 square pyramid, corners with four equivalent Cu(2)O5 trigonal bipyramids, and edges with four equivalent Cu(1)O5 trigonal bipyramids. In the third Cu site, Cu(3) is bonded in a square co-planar geometry to one O(3), one O(4), and two equivalent O(15) atoms. In the fourth Cu site, Cu(4) is bonded to one O(3), two equivalent O(1), and two equivalent O(11) atoms to form corner-sharing CuO5 square pyramids. In the fifth Cu site, Cu(5) is bonded to one O(4), two equivalent O(12), and two equivalent O(2) atoms to form corner-sharing CuO5 square pyramids. In the sixth Cu site, Cu(6) is bonded to one O(7), two equivalent O(13), and two equivalent O(9) atoms to form corner-sharing CuO5 square pyramids. There are fifteen inequivalent O sites. In the first O site, O(1) is bonded in a 6-coordinate geometry to two equivalent Ba(1), two equivalent Nd(1), and two equivalent Cu(4) atoms. In the second O site, O(2) is bonded in a 6-coordinate geometry to two equivalent Ba(2), two equivalent Nd(2), and two equivalent Cu(5) atoms. In the third O site, O(3) is bonded to four equivalent Ba(1), one Cu(3), and one Cu(4) atom to form a mixture of distorted face, corner, and edge-sharing OBa4Cu2 octahedra. The corner-sharing octahedral tilt angles range from 0-65°. In the fourth O site, O(4) is bonded to four equivalent Ba(2), one Cu(3), and one Cu(5) atom to form a mixture of distorted face, corner, and edge-sharing OBa4Cu2 octahedra. The corner-sharing octahedral tilt angles range from 0-66°. In the fifth O site, O(5) is bonded in a distorted see-saw-like geometry to two equivalent Cu(1) and two equivalent Cu(2) atoms. In the sixth O site, O(6) is bonded in a distorted see-saw-like geometry to two equivalent Cu(1) and two equivalent Cu(2) atoms. In the seventh O site, O(7) is bonded to four equivalent Ba(3), one Cu(1), and one Cu(6) atom to form a mixture of distorted corner and edge-sharing OBa4Cu2 octahedra. The corner-sharing octahedral tilt angles are 10°. In the eighth O site, O(8) is bonded to four equivalent Ba(4), one Ni(1), and one Cu(2) atom to form a mixture of corner and edge-sharing OBa4CuNi octahedra. The corner-sharing octahedral tilt angles are 8°. In the ninth O site, O(9) is bonded in a 6-coordinate geometry to two equivalent Ba(3), two equivalent Nd(1), and two equivalent Cu(6) atoms. In the tenth O site, O(10) is bonded in a 6-coordinate geometry to two equivalent Ba(4), two equivalent Nd(2), and two equivalent Ni(1) atoms. In the eleventh O site, O(11) is bonded in a 6-coordinate geometry to two equivalent Ba(1), two equivalent Nd(1), and two equivalent Cu(4) atoms. In the twelfth O site, O(12) is bonded in a 6-coordinate geometry to two equivalent Ba(2), two equivalent Nd(2), and two equivalent Cu(5) atoms. In the thirteenth O site, O(13) is bonded in a 6-coordinate geometry to two equivalent Ba(3), two equivalent Nd(1), and two equivalent Cu(6) atoms. In the fourteenth O site, O(14) is bonded in a 6-coordinate geometry to two equivalent Ba(4), two equivalent Nd(2), and two equivalent Ni(1) atoms. In the fifteenth O site, O(15) is bonded to two equivalent Ba(1), two equivalent Ba(2), and two equivalent Cu(3) atoms to form a mixture of distorted face, corner, and edge-sharing OBa4Cu2 octahedra. The corner-sharing octahedral tilt angles range from 1-66°.
Ba4Nd2NiCu6O15 crystallizes in the orthorhombic Imm2 space group. There are four inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 10-coordinate geometry to two equivalent O(1), two equivalent O(11), two equivalent O(15), and four equivalent O(3) atoms. Both Ba(1)-O(1) bond lengths are 3.00 Å. Both Ba(1)-O(11) bond lengths are 2.99 Å. Both Ba(1)-O(15) bond lengths are 2.86 Å. All Ba(1)-O(3) bond lengths are 2.78 Å. In the second Ba site, Ba(2) is bonded in a distorted q6 geometry to two equivalent O(12), two equivalent O(15), two equivalent O(2), and four equivalent O(4) atoms. Both Ba(2)-O(12) bond lengths are 2.98 Å. Both Ba(2)-O(15) bond lengths are 2.88 Å. Both Ba(2)-O(2) bond lengths are 2.98 Å. All Ba(2)-O(4) bond lengths are 2.79 Å. In the third Ba site, Ba(3) is bonded in a 8-coordinate geometry to two equivalent O(13), two equivalent O(9), and four equivalent O(7) atoms. Both Ba(3)-O(13) bond lengths are 2.96 Å. Both Ba(3)-O(9) bond lengths are 2.99 Å. All Ba(3)-O(7) bond lengths are 2.79 Å. In the fourth Ba site, Ba(4) is bonded in a 8-coordinate geometry to two equivalent O(10), two equivalent O(14), and four equivalent O(8) atoms. Both Ba(4)-O(10) bond lengths are 2.99 Å. Both Ba(4)-O(14) bond lengths are 2.97 Å. All Ba(4)-O(8) bond lengths are 2.78 Å. There are two inequivalent Nd sites. In the first Nd site, Nd(1) is bonded in a body-centered cubic geometry to two equivalent O(1), two equivalent O(11), two equivalent O(13), and two equivalent O(9) atoms. Both Nd(1)-O(1) bond lengths are 2.46 Å. Both Nd(1)-O(11) bond lengths are 2.49 Å. Both Nd(1)-O(13) bond lengths are 2.50 Å. Both Nd(1)-O(9) bond lengths are 2.50 Å. In the second Nd site, Nd(2) is bonded in a body-centered cubic geometry to two equivalent O(10), two equivalent O(12), two equivalent O(14), and two equivalent O(2) atoms. Both Nd(2)-O(10) bond lengths are 2.48 Å. Both Nd(2)-O(12) bond lengths are 2.51 Å. Both Nd(2)-O(14) bond lengths are 2.47 Å. Both Nd(2)-O(2) bond lengths are 2.48 Å. Ni(1) is bonded to one O(8), two equivalent O(10), and two equivalent O(14) atoms to form NiO5 square pyramids that share corners with four equivalent Ni(1)O5 square pyramids and  a cornercorner with one Cu(2)O5 trigonal bipyramid. The Ni(1)-O(8) bond length is 2.04 Å. Both Ni(1)-O(10) bond lengths are 2.00 Å. Both Ni(1)-O(14) bond lengths are 2.01 Å. There are six inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one O(7), two equivalent O(5), and two equivalent O(6) atoms to form a mixture of distorted corner and edge-sharing CuO5 trigonal bipyramids. The Cu(1)-O(7) bond length is 1.99 Å. Both Cu(1)-O(5) bond lengths are 2.00 Å. Both Cu(1)-O(6) bond lengths are 2.12 Å. In the second Cu site, Cu(2) is bonded to one O(8), two equivalent O(5), and two equivalent O(6) atoms to form distorted CuO5 trigonal bipyramids that share  a cornercorner with one Ni(1)O5 square pyramid, corners with four equivalent Cu(2)O5 trigonal bipyramids, and edges with four equivalent Cu(1)O5 trigonal bipyramids. The Cu(2)-O(8) bond length is 2.04 Å. Both Cu(2)-O(5) bond lengths are 2.12 Å. Both Cu(2)-O(6) bond lengths are 2.00 Å. In the third Cu site, Cu(3) is bonded in a square co-planar geometry to one O(3), one O(4), and two equivalent O(15) atoms. The Cu(3)-O(3) bond length is 1.88 Å. The Cu(3)-O(4) bond length is 1.86 Å. Both Cu(3)-O(15) bond lengths are 1.97 Å. In the fourth Cu site, Cu(4) is bonded to one O(3), two equivalent O(1), and two equivalent O(11) atoms to form corner-sharing CuO5 square pyramids. The Cu(4)-O(3) bond length is 2.17 Å. Both Cu(4)-O(1) bond lengths are 2.00 Å. Both Cu(4)-O(11) bond lengths are 1.98 Å. In the fifth Cu site, Cu(5) is bonded to one O(4), two equivalent O(12), and two equivalent O(2) atoms to form corner-sharing CuO5 square pyramids. The Cu(5)-O(4) bond length is 2.18 Å. Both Cu(5)-O(12) bond lengths are 1.98 Å. Both Cu(5)-O(2) bond lengths are 2.00 Å. In the sixth Cu site, Cu(6) is bonded to one O(7), two equivalent O(13), and two equivalent O(9) atoms to form corner-sharing CuO5 square pyramids. The Cu(6)-O(7) bond length is 2.20 Å. Both Cu(6)-O(13) bond lengths are 1.99 Å. Both Cu(6)-O(9) bond lengths are 1.98 Å. There are fifteen inequivalent O sites. In the first O site, O(1) is bonded in a 6-coordinate geometry to two equivalent Ba(1), two equivalent Nd(1), and two equivalent Cu(4) atoms. In the second O site, O(2) is bonded in a 6-coordinate geometry to two equivalent Ba(2), two equivalent Nd(2), and two equivalent Cu(5) atoms. In the third O site, O(3) is bonded to four equivalent Ba(1), one Cu(3), and one Cu(4) atom to form a mixture of distorted face, corner, and edge-sharing OBa4Cu2 octahedra. The corner-sharing octahedral tilt angles range from 0-65°. In the fourth O site, O(4) is bonded to four equivalent Ba(2), one Cu(3), and one Cu(5) atom to form a mixture of distorted face, corner, and edge-sharing OBa4Cu2 octahedra. The corner-sharing octahedral tilt angles range from 0-66°. In the fifth O site, O(5) is bonded in a distorted see-saw-like geometry to two equivalent Cu(1) and two equivalent Cu(2) atoms. In the sixth O site, O(6) is bonded in a distorted see-saw-like geometry to two equivalent Cu(1) and two equivalent Cu(2) atoms. In the seventh O site, O(7) is bonded to four equivalent Ba(3), one Cu(1), and one Cu(6) atom to form a mixture of distorted corner and edge-sharing OBa4Cu2 octahedra. The corner-sharing octahedral tilt angles are 10°. In the eighth O site, O(8) is bonded to four equivalent Ba(4), one Ni(1), and one Cu(2) atom to form a mixture of corner and edge-sharing OBa4CuNi octahedra. The corner-sharing octahedral tilt angles are 8°. In the ninth O site, O(9) is bonded in a 6-coordinate geometry to two equivalent Ba(3), two equivalent Nd(1), and two equivalent Cu(6) atoms. In the tenth O site, O(10) is bonded in a 6-coordinate geometry to two equivalent Ba(4), two equivalent Nd(2), and two equivalent Ni(1) atoms. In the eleventh O site, O(11) is bonded in a 6-coordinate geometry to two equivalent Ba(1), two equivalent Nd(1), and two equivalent Cu(4) atoms. In the twelfth O site, O(12) is bonded in a 6-coordinate geometry to two equivalent Ba(2), two equivalent Nd(2), and two equivalent Cu(5) atoms. In the thirteenth O site, O(13) is bonded in a 6-coordinate geometry to two equivalent Ba(3), two equivalent Nd(1), and two equivalent Cu(6) atoms. In the fourteenth O site, O(14) is bonded in a 6-coordinate geometry to two equivalent Ba(4), two equivalent Nd(2), and two equivalent Ni(1) atoms. In the fifteenth O site, O(15) is bonded to two equivalent Ba(1), two equivalent Ba(2), and two equivalent Cu(3) atoms to form a mixture of distorted face, corner, and edge-sharing OBa4Cu2 octahedra. The corner-sharing octahedral tilt angles range from 1-66°.