Ba6CaEu2Cu6(HgO7)3 crystallizes in the monoclinic C2/m space group. There are three inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 9-coordinate geometry to one O(1), one O(3), one O(8), two equivalent O(2), two equivalent O(4), and two equivalent O(5) atoms. In the second Ba site, Ba(2) is bonded in a 9-coordinate geometry to one O(1), one O(2), one O(7), two equivalent O(3), two equivalent O(5), and two equivalent O(6) atoms. In the third Ba site, Ba(3) is bonded in a 9-coordinate geometry to one O(2), one O(3), one O(8), two equivalent O(1), two equivalent O(4), and two equivalent O(6) atoms. Ca(1) is bonded in a body-centered cubic geometry to four equivalent O(4) and four equivalent O(6) atoms. Eu(1) is bonded in a body-centered cubic geometry to two equivalent O(4), two equivalent O(6), and four equivalent O(5) atoms. There are three inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one O(1), two equivalent O(4), and two equivalent O(6) atoms to form distorted corner-sharing CuO5 square pyramids. In the second Cu site, Cu(2) is bonded to one O(2), two equivalent O(4), and two equivalent O(5) atoms to form distorted corner-sharing CuO5 square pyramids. In the third Cu site, Cu(3) is bonded to one O(3), two equivalent O(5), and two equivalent O(6) atoms to form distorted corner-sharing CuO5 square pyramids. There are two inequivalent Hg sites. In the first Hg site, Hg(1) is bonded in a linear geometry to one O(1) and one O(2) atom. In the second Hg site, Hg(2) is bonded in a linear geometry to two equivalent O(3) atoms. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a 6-coordinate geometry to one Ba(1), one Ba(2), two equivalent Ba(3), one Cu(1), and one Hg(1) atom. In the second O site, O(2) is bonded to one Ba(2), one Ba(3), two equivalent Ba(1), one Cu(2), and one Hg(1) atom to form distorted corner-sharing OBa4CuHg octahedra. The corner-sharing octahedral tilt angles are 21°. In the third O site, O(3) is bonded in a 6-coordinate geometry to one Ba(1), one Ba(3), two equivalent Ba(2), one Cu(3), and one Hg(2) atom. In the fourth O site, O(4) is bonded in a 6-coordinate geometry to one Ba(1), one Ba(3), one Ca(1), one Eu(1), one Cu(1), and one Cu(2) atom. In the fifth O site, O(5) is bonded in a 6-coordinate geometry to one Ba(1), one Ba(2), two equivalent Eu(1), one Cu(2), and one Cu(3) atom. In the sixth O site, O(6) is bonded in a 6-coordinate geometry to one Ba(2), one Ba(3), one Ca(1), one Eu(1), one Cu(1), and one Cu(3) atom. In the seventh O site, O(7) is bonded in a distorted linear geometry to two equivalent Ba(2) atoms. In the eighth O site, O(8) is bonded in a distorted linear geometry to one Ba(1) and one Ba(3) atom.
Ba6CaEu2Cu6(HgO7)3 crystallizes in the monoclinic C2/m space group. There are three inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 9-coordinate geometry to one O(1), one O(3), one O(8), two equivalent O(2), two equivalent O(4), and two equivalent O(5) atoms. The Ba(1)-O(1) bond length is 2.77 Å. The Ba(1)-O(3) bond length is 2.78 Å. The Ba(1)-O(8) bond length is 2.61 Å. Both Ba(1)-O(2) bond lengths are 2.77 Å. Both Ba(1)-O(4) bond lengths are 2.99 Å. Both Ba(1)-O(5) bond lengths are 3.01 Å. In the second Ba site, Ba(2) is bonded in a 9-coordinate geometry to one O(1), one O(2), one O(7), two equivalent O(3), two equivalent O(5), and two equivalent O(6) atoms. The Ba(2)-O(1) bond length is 2.77 Å. The Ba(2)-O(2) bond length is 2.78 Å. The Ba(2)-O(7) bond length is 2.60 Å. Both Ba(2)-O(3) bond lengths are 2.77 Å. Both Ba(2)-O(5) bond lengths are 3.01 Å. Both Ba(2)-O(6) bond lengths are 2.98 Å. In the third Ba site, Ba(3) is bonded in a 9-coordinate geometry to one O(2), one O(3), one O(8), two equivalent O(1), two equivalent O(4), and two equivalent O(6) atoms. The Ba(3)-O(2) bond length is 2.78 Å. The Ba(3)-O(3) bond length is 2.78 Å. The Ba(3)-O(8) bond length is 2.62 Å. Both Ba(3)-O(1) bond lengths are 2.78 Å. Both Ba(3)-O(4) bond lengths are 2.98 Å. Both Ba(3)-O(6) bond lengths are 2.98 Å. Ca(1) is bonded in a body-centered cubic geometry to four equivalent O(4) and four equivalent O(6) atoms. All Ca(1)-O(4) bond lengths are 2.47 Å. All Ca(1)-O(6) bond lengths are 2.47 Å. Eu(1) is bonded in a body-centered cubic geometry to two equivalent O(4), two equivalent O(6), and four equivalent O(5) atoms. Both Eu(1)-O(4) bond lengths are 2.44 Å. Both Eu(1)-O(6) bond lengths are 2.44 Å. All Eu(1)-O(5) bond lengths are 2.46 Å. There are three inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one O(1), two equivalent O(4), and two equivalent O(6) atoms to form distorted corner-sharing CuO5 square pyramids. The Cu(1)-O(1) bond length is 2.62 Å. Both Cu(1)-O(4) bond lengths are 1.94 Å. Both Cu(1)-O(6) bond lengths are 1.94 Å. In the second Cu site, Cu(2) is bonded to one O(2), two equivalent O(4), and two equivalent O(5) atoms to form distorted corner-sharing CuO5 square pyramids. The Cu(2)-O(2) bond length is 2.61 Å. Both Cu(2)-O(4) bond lengths are 1.93 Å. Both Cu(2)-O(5) bond lengths are 1.95 Å. In the third Cu site, Cu(3) is bonded to one O(3), two equivalent O(5), and two equivalent O(6) atoms to form distorted corner-sharing CuO5 square pyramids. The Cu(3)-O(3) bond length is 2.62 Å. Both Cu(3)-O(5) bond lengths are 1.95 Å. Both Cu(3)-O(6) bond lengths are 1.93 Å. There are two inequivalent Hg sites. In the first Hg site, Hg(1) is bonded in a linear geometry to one O(1) and one O(2) atom. The Hg(1)-O(1) bond length is 2.09 Å. The Hg(1)-O(2) bond length is 2.11 Å. In the second Hg site, Hg(2) is bonded in a linear geometry to two equivalent O(3) atoms. Both Hg(2)-O(3) bond lengths are 2.10 Å. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a 6-coordinate geometry to one Ba(1), one Ba(2), two equivalent Ba(3), one Cu(1), and one Hg(1) atom. In the second O site, O(2) is bonded to one Ba(2), one Ba(3), two equivalent Ba(1), one Cu(2), and one Hg(1) atom to form distorted corner-sharing OBa4CuHg octahedra. The corner-sharing octahedral tilt angles are 21°. In the third O site, O(3) is bonded in a 6-coordinate geometry to one Ba(1), one Ba(3), two equivalent Ba(2), one Cu(3), and one Hg(2) atom. In the fourth O site, O(4) is bonded in a 6-coordinate geometry to one Ba(1), one Ba(3), one Ca(1), one Eu(1), one Cu(1), and one Cu(2) atom. In the fifth O site, O(5) is bonded in a 6-coordinate geometry to one Ba(1), one Ba(2), two equivalent Eu(1), one Cu(2), and one Cu(3) atom. In the sixth O site, O(6) is bonded in a 6-coordinate geometry to one Ba(2), one Ba(3), one Ca(1), one Eu(1), one Cu(1), and one Cu(3) atom. In the seventh O site, O(7) is bonded in a distorted linear geometry to two equivalent Ba(2) atoms. In the eighth O site, O(8) is bonded in a distorted linear geometry to one Ba(1) and one Ba(3) atom.