Ba5MgBi3O11 crystallizes in the triclinic P1 space group. There are five inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 7-coordinate geometry to one O(1), one O(3), one O(4), one O(5), one O(6), one O(7), and one O(8) atom. In the second Ba site, Ba(2) is bonded in a 6-coordinate geometry to one O(1), one O(10), one O(11), one O(2), one O(3), and one O(7) atom. In the third Ba site, Ba(3) is bonded to one O(11), one O(4), one O(5), one O(8), and one O(9) atom to form distorted BaO5 square pyramids that share  a cornercorner with one Bi(1)O5 square pyramid,  a cornercorner with one Mg(1)O4 tetrahedra, and  an edgeedge with one Mg(1)O4 tetrahedra. In the fourth Ba site, Ba(4) is bonded in a 8-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), one O(6), one O(8), and one O(9) atom. In the fifth Ba site, Ba(5) is bonded in a 6-coordinate geometry to one O(10), one O(11), one O(2), one O(3), one O(7), and one O(9) atom. Mg(1) is bonded to one O(10), one O(11), one O(8), and one O(9) atom to form MgO4 tetrahedra that share  a cornercorner with one Bi(2)O6 octahedra,  a cornercorner with one Ba(3)O5 square pyramid, and  an edgeedge with one Ba(3)O5 square pyramid. The corner-sharing octahedral tilt angles are 38°. There are three inequivalent Bi sites. In the first Bi site, Bi(1) is bonded to one O(1), one O(2), one O(3), one O(4), and one O(7) atom to form BiO5 square pyramids that share corners with four equivalent Bi(2)O6 octahedra and  a cornercorner with one Ba(3)O5 square pyramid. The corner-sharing octahedral tilt angles range from 17-26°. In the second Bi site, Bi(2) is bonded to one O(1), one O(10), one O(2), one O(3), one O(6), and one O(7) atom to form BiO6 octahedra that share corners with four equivalent Bi(1)O5 square pyramids and  a cornercorner with one Mg(1)O4 tetrahedra. In the third Bi site, Bi(3) is bonded in a distorted rectangular see-saw-like geometry to one O(5), one O(6), one O(8), and one O(9) atom. There are eleven inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to one Ba(1), one Ba(2), one Ba(4), one Bi(1), and one Bi(2) atom. In the second O site, O(2) is bonded in a 5-coordinate geometry to one Ba(2), one Ba(4), one Ba(5), one Bi(1), and one Bi(2) atom. In the third O site, O(3) is bonded to one Ba(1), one Ba(2), one Ba(4), one Ba(5), one Bi(1), and one Bi(2) atom to form a mixture of distorted corner and edge-sharing OBa4Bi2 octahedra. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Ba(1), one Ba(3), one Ba(4), and one Bi(1) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Ba(1), one Ba(3), one Ba(4), and one Bi(3) atom. In the sixth O site, O(6) is bonded to one Ba(1), one Ba(4), one Bi(2), and one Bi(3) atom to form a mixture of distorted corner and edge-sharing OBa2Bi2 tetrahedra. The corner-sharing octahedral tilt angles are 69°. In the seventh O site, O(7) is bonded in a 5-coordinate geometry to one Ba(1), one Ba(2), one Ba(5), one Bi(1), and one Bi(2) atom. In the eighth O site, O(8) is bonded in a 5-coordinate geometry to one Ba(1), one Ba(3), one Ba(4), one Mg(1), and one Bi(3) atom. In the ninth O site, O(9) is bonded in a 5-coordinate geometry to one Ba(3), one Ba(4), one Ba(5), one Mg(1), and one Bi(3) atom. In the tenth O site, O(10) is bonded in a 4-coordinate geometry to one Ba(2), one Ba(5), one Mg(1), and one Bi(2) atom. In the eleventh O site, O(11) is bonded in a distorted see-saw-like geometry to one Ba(2), one Ba(3), one Ba(5), and one Mg(1) atom.
Ba5MgBi3O11 crystallizes in the triclinic P1 space group. There are five inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 7-coordinate geometry to one O(1), one O(3), one O(4), one O(5), one O(6), one O(7), and one O(8) atom. The Ba(1)-O(1) bond length is 2.91 Å. The Ba(1)-O(3) bond length is 2.87 Å. The Ba(1)-O(4) bond length is 2.75 Å. The Ba(1)-O(5) bond length is 2.62 Å. The Ba(1)-O(6) bond length is 2.79 Å. The Ba(1)-O(7) bond length is 3.25 Å. The Ba(1)-O(8) bond length is 3.11 Å. In the second Ba site, Ba(2) is bonded in a 6-coordinate geometry to one O(1), one O(10), one O(11), one O(2), one O(3), and one O(7) atom. The Ba(2)-O(1) bond length is 2.78 Å. The Ba(2)-O(10) bond length is 2.85 Å. The Ba(2)-O(11) bond length is 2.54 Å. The Ba(2)-O(2) bond length is 2.86 Å. The Ba(2)-O(3) bond length is 3.28 Å. The Ba(2)-O(7) bond length is 2.67 Å. In the third Ba site, Ba(3) is bonded to one O(11), one O(4), one O(5), one O(8), and one O(9) atom to form distorted BaO5 square pyramids that share  a cornercorner with one Bi(1)O5 square pyramid,  a cornercorner with one Mg(1)O4 tetrahedra, and  an edgeedge with one Mg(1)O4 tetrahedra. The Ba(3)-O(11) bond length is 2.57 Å. The Ba(3)-O(4) bond length is 2.55 Å. The Ba(3)-O(5) bond length is 2.65 Å. The Ba(3)-O(8) bond length is 2.77 Å. The Ba(3)-O(9) bond length is 2.58 Å. In the fourth Ba site, Ba(4) is bonded in a 8-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), one O(6), one O(8), and one O(9) atom. The Ba(4)-O(1) bond length is 3.01 Å. The Ba(4)-O(2) bond length is 3.32 Å. The Ba(4)-O(3) bond length is 2.83 Å. The Ba(4)-O(4) bond length is 3.09 Å. The Ba(4)-O(5) bond length is 3.33 Å. The Ba(4)-O(6) bond length is 2.69 Å. The Ba(4)-O(8) bond length is 2.74 Å. The Ba(4)-O(9) bond length is 3.06 Å. In the fifth Ba site, Ba(5) is bonded in a 6-coordinate geometry to one O(10), one O(11), one O(2), one O(3), one O(7), and one O(9) atom. The Ba(5)-O(10) bond length is 2.92 Å. The Ba(5)-O(11) bond length is 2.64 Å. The Ba(5)-O(2) bond length is 2.73 Å. The Ba(5)-O(3) bond length is 2.88 Å. The Ba(5)-O(7) bond length is 2.76 Å. The Ba(5)-O(9) bond length is 2.98 Å. Mg(1) is bonded to one O(10), one O(11), one O(8), and one O(9) atom to form MgO4 tetrahedra that share  a cornercorner with one Bi(2)O6 octahedra,  a cornercorner with one Ba(3)O5 square pyramid, and  an edgeedge with one Ba(3)O5 square pyramid. The corner-sharing octahedral tilt angles are 38°. The Mg(1)-O(10) bond length is 2.06 Å. The Mg(1)-O(11) bond length is 2.00 Å. The Mg(1)-O(8) bond length is 2.01 Å. The Mg(1)-O(9) bond length is 1.99 Å. There are three inequivalent Bi sites. In the first Bi site, Bi(1) is bonded to one O(1), one O(2), one O(3), one O(4), and one O(7) atom to form BiO5 square pyramids that share corners with four equivalent Bi(2)O6 octahedra and  a cornercorner with one Ba(3)O5 square pyramid. The corner-sharing octahedral tilt angles range from 17-26°. The Bi(1)-O(1) bond length is 2.34 Å. The Bi(1)-O(2) bond length is 2.28 Å. The Bi(1)-O(3) bond length is 2.43 Å. The Bi(1)-O(4) bond length is 2.09 Å. The Bi(1)-O(7) bond length is 2.32 Å. In the second Bi site, Bi(2) is bonded to one O(1), one O(10), one O(2), one O(3), one O(6), and one O(7) atom to form BiO6 octahedra that share corners with four equivalent Bi(1)O5 square pyramids and  a cornercorner with one Mg(1)O4 tetrahedra. The Bi(2)-O(1) bond length is 2.33 Å. The Bi(2)-O(10) bond length is 2.25 Å. The Bi(2)-O(2) bond length is 2.30 Å. The Bi(2)-O(3) bond length is 2.35 Å. The Bi(2)-O(6) bond length is 2.59 Å. The Bi(2)-O(7) bond length is 2.31 Å. In the third Bi site, Bi(3) is bonded in a distorted rectangular see-saw-like geometry to one O(5), one O(6), one O(8), and one O(9) atom. The Bi(3)-O(5) bond length is 2.11 Å. The Bi(3)-O(6) bond length is 2.13 Å. The Bi(3)-O(8) bond length is 2.29 Å. The Bi(3)-O(9) bond length is 2.38 Å. There are eleven inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to one Ba(1), one Ba(2), one Ba(4), one Bi(1), and one Bi(2) atom. In the second O site, O(2) is bonded in a 5-coordinate geometry to one Ba(2), one Ba(4), one Ba(5), one Bi(1), and one Bi(2) atom. In the third O site, O(3) is bonded to one Ba(1), one Ba(2), one Ba(4), one Ba(5), one Bi(1), and one Bi(2) atom to form a mixture of distorted corner and edge-sharing OBa4Bi2 octahedra. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Ba(1), one Ba(3), one Ba(4), and one Bi(1) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Ba(1), one Ba(3), one Ba(4), and one Bi(3) atom. In the sixth O site, O(6) is bonded to one Ba(1), one Ba(4), one Bi(2), and one Bi(3) atom to form a mixture of distorted corner and edge-sharing OBa2Bi2 tetrahedra. The corner-sharing octahedral tilt angles are 69°. In the seventh O site, O(7) is bonded in a 5-coordinate geometry to one Ba(1), one Ba(2), one Ba(5), one Bi(1), and one Bi(2) atom. In the eighth O site, O(8) is bonded in a 5-coordinate geometry to one Ba(1), one Ba(3), one Ba(4), one Mg(1), and one Bi(3) atom. In the ninth O site, O(9) is bonded in a 5-coordinate geometry to one Ba(3), one Ba(4), one Ba(5), one Mg(1), and one Bi(3) atom. In the tenth O site, O(10) is bonded in a 4-coordinate geometry to one Ba(2), one Ba(5), one Mg(1), and one Bi(2) atom. In the eleventh O site, O(11) is bonded in a distorted see-saw-like geometry to one Ba(2), one Ba(3), one Ba(5), and one Mg(1) atom.