MgZn2Bi3O8 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), one O(2), one O(5), one O(6), one O(7), and one O(8) atom to form MgO6 octahedra that share edges with two equivalent Bi(1)O6 octahedra, edges with two equivalent Bi(2)O6 octahedra, and edges with two equivalent Bi(3)O6 octahedra. There are two inequivalent Zn sites. In the first Zn site, Zn(1) is bonded in a distorted trigonal planar geometry to one O(3), one O(5), and one O(6) atom. In the second Zn site, Zn(2) is bonded in a distorted trigonal planar geometry to one O(4), one O(7), and one O(8) atom. There are three inequivalent Bi sites. In the first Bi site, Bi(1) is bonded to one O(3), one O(4), one O(5), one O(6), one O(7), and one O(8) atom to form BiO6 octahedra that share edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Bi(2)O6 octahedra, and edges with two equivalent Bi(3)O6 octahedra. In the second Bi site, Bi(2) is bonded to one O(1), one O(2), one O(3), one O(4), one O(6), and one O(8) atom to form BiO6 octahedra that share edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Bi(1)O6 octahedra, and edges with two equivalent Bi(3)O6 octahedra. In the third Bi site, Bi(3) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(7) atom to form BiO6 octahedra that share edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Bi(1)O6 octahedra, and edges with two equivalent Bi(2)O6 octahedra. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to one Mg(1), one Bi(2), and one Bi(3) atom. In the second O site, O(2) is bonded in a distorted T-shaped geometry to one Mg(1), one Bi(2), and one Bi(3) atom. In the third O site, O(3) is bonded in a distorted rectangular see-saw-like geometry to one Zn(1), one Bi(1), one Bi(2), and one Bi(3) atom. In the fourth O site, O(4) is bonded in a distorted rectangular see-saw-like geometry to one Zn(2), one Bi(1), one Bi(2), and one Bi(3) atom. In the fifth O site, O(5) is bonded to one Mg(1), one Zn(1), one Bi(1), and one Bi(3) atom to form a mixture of distorted corner and edge-sharing OMgZnBi2 trigonal pyramids. In the sixth O site, O(6) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Zn(1), one Bi(1), and one Bi(2) atom. In the seventh O site, O(7) is bonded to one Mg(1), one Zn(2), one Bi(1), and one Bi(3) atom to form a mixture of distorted corner and edge-sharing OMgZnBi2 trigonal pyramids. In the eighth O site, O(8) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Zn(2), one Bi(1), and one Bi(2) atom.
MgZn2Bi3O8 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), one O(2), one O(5), one O(6), one O(7), and one O(8) atom to form MgO6 octahedra that share edges with two equivalent Bi(1)O6 octahedra, edges with two equivalent Bi(2)O6 octahedra, and edges with two equivalent Bi(3)O6 octahedra. The Mg(1)-O(1) bond length is 2.25 Å. The Mg(1)-O(2) bond length is 2.25 Å. The Mg(1)-O(5) bond length is 2.10 Å. The Mg(1)-O(6) bond length is 2.12 Å. The Mg(1)-O(7) bond length is 2.10 Å. The Mg(1)-O(8) bond length is 2.12 Å. There are two inequivalent Zn sites. In the first Zn site, Zn(1) is bonded in a distorted trigonal planar geometry to one O(3), one O(5), and one O(6) atom. The Zn(1)-O(3) bond length is 1.87 Å. The Zn(1)-O(5) bond length is 1.97 Å. The Zn(1)-O(6) bond length is 2.00 Å. In the second Zn site, Zn(2) is bonded in a distorted trigonal planar geometry to one O(4), one O(7), and one O(8) atom. The Zn(2)-O(4) bond length is 1.87 Å. The Zn(2)-O(7) bond length is 1.97 Å. The Zn(2)-O(8) bond length is 2.00 Å. There are three inequivalent Bi sites. In the first Bi site, Bi(1) is bonded to one O(3), one O(4), one O(5), one O(6), one O(7), and one O(8) atom to form BiO6 octahedra that share edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Bi(2)O6 octahedra, and edges with two equivalent Bi(3)O6 octahedra. The Bi(1)-O(3) bond length is 2.36 Å. The Bi(1)-O(4) bond length is 2.37 Å. The Bi(1)-O(5) bond length is 2.64 Å. The Bi(1)-O(6) bond length is 2.35 Å. The Bi(1)-O(7) bond length is 2.64 Å. The Bi(1)-O(8) bond length is 2.35 Å. In the second Bi site, Bi(2) is bonded to one O(1), one O(2), one O(3), one O(4), one O(6), and one O(8) atom to form BiO6 octahedra that share edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Bi(1)O6 octahedra, and edges with two equivalent Bi(3)O6 octahedra. The Bi(2)-O(1) bond length is 2.21 Å. The Bi(2)-O(2) bond length is 2.21 Å. The Bi(2)-O(3) bond length is 2.57 Å. The Bi(2)-O(4) bond length is 2.57 Å. The Bi(2)-O(6) bond length is 2.40 Å. The Bi(2)-O(8) bond length is 2.39 Å. In the third Bi site, Bi(3) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(7) atom to form BiO6 octahedra that share edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Bi(1)O6 octahedra, and edges with two equivalent Bi(2)O6 octahedra. The Bi(3)-O(1) bond length is 2.20 Å. The Bi(3)-O(2) bond length is 2.20 Å. The Bi(3)-O(3) bond length is 2.41 Å. The Bi(3)-O(4) bond length is 2.41 Å. The Bi(3)-O(5) bond length is 2.32 Å. The Bi(3)-O(7) bond length is 2.32 Å. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to one Mg(1), one Bi(2), and one Bi(3) atom. In the second O site, O(2) is bonded in a distorted T-shaped geometry to one Mg(1), one Bi(2), and one Bi(3) atom. In the third O site, O(3) is bonded in a distorted rectangular see-saw-like geometry to one Zn(1), one Bi(1), one Bi(2), and one Bi(3) atom. In the fourth O site, O(4) is bonded in a distorted rectangular see-saw-like geometry to one Zn(2), one Bi(1), one Bi(2), and one Bi(3) atom. In the fifth O site, O(5) is bonded to one Mg(1), one Zn(1), one Bi(1), and one Bi(3) atom to form a mixture of distorted corner and edge-sharing OMgZnBi2 trigonal pyramids. In the sixth O site, O(6) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Zn(1), one Bi(1), and one Bi(2) atom. In the seventh O site, O(7) is bonded to one Mg(1), one Zn(2), one Bi(1), and one Bi(3) atom to form a mixture of distorted corner and edge-sharing OMgZnBi2 trigonal pyramids. In the eighth O site, O(8) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Zn(2), one Bi(1), and one Bi(2) atom.