MgCo3TeO8 is beta indium sulfide-derived structured and crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), one O(2), one O(4), and one O(6) atom to form MgO4 tetrahedra that share corners with three equivalent Co(1)O6 octahedra, corners with three equivalent Co(2)O6 octahedra, corners with three equivalent Co(3)O6 octahedra, and corners with three equivalent Te(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 57-63°. There are three inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(1), one O(3), one O(4), one O(5), one O(6), and one O(8) atom to form CoO6 octahedra that share corners with three equivalent Mg(1)O4 tetrahedra, edges with two equivalent Co(2)O6 octahedra, edges with two equivalent Co(3)O6 octahedra, and edges with two equivalent Te(1)O6 octahedra. In the second Co site, Co(2) is bonded to one O(2), one O(3), one O(4), one O(5), one O(6), and one O(7) atom to form CoO6 octahedra that share corners with three equivalent Mg(1)O4 tetrahedra, edges with two equivalent Co(1)O6 octahedra, edges with two equivalent Co(3)O6 octahedra, and edges with two equivalent Te(1)O6 octahedra. In the third Co site, Co(3) is bonded to one O(1), one O(2), one O(3), one O(6), one O(7), and one O(8) atom to form CoO6 octahedra that share corners with three equivalent Mg(1)O4 tetrahedra, edges with two equivalent Co(1)O6 octahedra, edges with two equivalent Co(2)O6 octahedra, and edges with two equivalent Te(1)O6 octahedra. Te(1) is bonded to one O(1), one O(2), one O(4), one O(5), one O(7), and one O(8) atom to form TeO6 octahedra that share corners with three equivalent Mg(1)O4 tetrahedra, edges with two equivalent Co(1)O6 octahedra, edges with two equivalent Co(2)O6 octahedra, and edges with two equivalent Co(3)O6 octahedra. There are eight inequivalent O sites. In the first O site, O(1) is bonded to one Mg(1), one Co(1), one Co(3), and one Te(1) atom to form distorted OMgCo2Te trigonal pyramids that share  a cornercorner with one O(6)MgCo3 tetrahedra,  a cornercorner with one O(2)MgCo2Te trigonal pyramid,  a cornercorner with one O(4)MgCo2Te trigonal pyramid,  an edgeedge with one O(6)MgCo3 tetrahedra,  an edgeedge with one O(2)MgCo2Te trigonal pyramid, and  an edgeedge with one O(4)MgCo2Te trigonal pyramid. In the second O site, O(2) is bonded to one Mg(1), one Co(2), one Co(3), and one Te(1) atom to form distorted OMgCo2Te trigonal pyramids that share  a cornercorner with one O(6)MgCo3 tetrahedra,  a cornercorner with one O(1)MgCo2Te trigonal pyramid,  a cornercorner with one O(4)MgCo2Te trigonal pyramid,  an edgeedge with one O(6)MgCo3 tetrahedra,  an edgeedge with one O(1)MgCo2Te trigonal pyramid, and  an edgeedge with one O(4)MgCo2Te trigonal pyramid. In the third O site, O(3) is bonded in a distorted trigonal non-coplanar geometry to one Co(1), one Co(2), and one Co(3) atom. In the fourth O site, O(4) is bonded to one Mg(1), one Co(1), one Co(2), and one Te(1) atom to form distorted OMgCo2Te trigonal pyramids that share  a cornercorner with one O(6)MgCo3 tetrahedra,  a cornercorner with one O(1)MgCo2Te trigonal pyramid,  a cornercorner with one O(2)MgCo2Te trigonal pyramid,  an edgeedge with one O(6)MgCo3 tetrahedra,  an edgeedge with one O(1)MgCo2Te trigonal pyramid, and  an edgeedge with one O(2)MgCo2Te trigonal pyramid. In the fifth O site, O(5) is bonded in a distorted T-shaped geometry to one Co(1), one Co(2), and one Te(1) atom. In the sixth O site, O(6) is bonded to one Mg(1), one Co(1), one Co(2), and one Co(3) atom to form a mixture of corner and edge-sharing OMgCo3 tetrahedra. In the seventh O site, O(7) is bonded in a distorted T-shaped geometry to one Co(2), one Co(3), and one Te(1) atom. In the eighth O site, O(8) is bonded in a distorted T-shaped geometry to one Co(1), one Co(3), and one Te(1) atom.
MgCo3TeO8 is beta indium sulfide-derived structured and crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), one O(2), one O(4), and one O(6) atom to form MgO4 tetrahedra that share corners with three equivalent Co(1)O6 octahedra, corners with three equivalent Co(2)O6 octahedra, corners with three equivalent Co(3)O6 octahedra, and corners with three equivalent Te(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 57-63°. The Mg(1)-O(1) bond length is 2.06 Å. The Mg(1)-O(2) bond length is 2.02 Å. The Mg(1)-O(4) bond length is 2.03 Å. The Mg(1)-O(6) bond length is 2.00 Å. There are three inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(1), one O(3), one O(4), one O(5), one O(6), and one O(8) atom to form CoO6 octahedra that share corners with three equivalent Mg(1)O4 tetrahedra, edges with two equivalent Co(2)O6 octahedra, edges with two equivalent Co(3)O6 octahedra, and edges with two equivalent Te(1)O6 octahedra. The Co(1)-O(1) bond length is 2.17 Å. The Co(1)-O(3) bond length is 1.89 Å. The Co(1)-O(4) bond length is 2.18 Å. The Co(1)-O(5) bond length is 2.04 Å. The Co(1)-O(6) bond length is 1.97 Å. The Co(1)-O(8) bond length is 2.07 Å. In the second Co site, Co(2) is bonded to one O(2), one O(3), one O(4), one O(5), one O(6), and one O(7) atom to form CoO6 octahedra that share corners with three equivalent Mg(1)O4 tetrahedra, edges with two equivalent Co(1)O6 octahedra, edges with two equivalent Co(3)O6 octahedra, and edges with two equivalent Te(1)O6 octahedra. The Co(2)-O(2) bond length is 2.15 Å. The Co(2)-O(3) bond length is 2.05 Å. The Co(2)-O(4) bond length is 2.14 Å. The Co(2)-O(5) bond length is 2.13 Å. The Co(2)-O(6) bond length is 2.08 Å. The Co(2)-O(7) bond length is 2.14 Å. In the third Co site, Co(3) is bonded to one O(1), one O(2), one O(3), one O(6), one O(7), and one O(8) atom to form CoO6 octahedra that share corners with three equivalent Mg(1)O4 tetrahedra, edges with two equivalent Co(1)O6 octahedra, edges with two equivalent Co(2)O6 octahedra, and edges with two equivalent Te(1)O6 octahedra. The Co(3)-O(1) bond length is 2.17 Å. The Co(3)-O(2) bond length is 2.17 Å. The Co(3)-O(3) bond length is 1.89 Å. The Co(3)-O(6) bond length is 1.98 Å. The Co(3)-O(7) bond length is 2.04 Å. The Co(3)-O(8) bond length is 2.07 Å. Te(1) is bonded to one O(1), one O(2), one O(4), one O(5), one O(7), and one O(8) atom to form TeO6 octahedra that share corners with three equivalent Mg(1)O4 tetrahedra, edges with two equivalent Co(1)O6 octahedra, edges with two equivalent Co(2)O6 octahedra, and edges with two equivalent Co(3)O6 octahedra. The Te(1)-O(1) bond length is 2.00 Å. The Te(1)-O(2) bond length is 1.98 Å. The Te(1)-O(4) bond length is 1.98 Å. The Te(1)-O(5) bond length is 1.95 Å. The Te(1)-O(7) bond length is 1.95 Å. The Te(1)-O(8) bond length is 1.97 Å. There are eight inequivalent O sites. In the first O site, O(1) is bonded to one Mg(1), one Co(1), one Co(3), and one Te(1) atom to form distorted OMgCo2Te trigonal pyramids that share  a cornercorner with one O(6)MgCo3 tetrahedra,  a cornercorner with one O(2)MgCo2Te trigonal pyramid,  a cornercorner with one O(4)MgCo2Te trigonal pyramid,  an edgeedge with one O(6)MgCo3 tetrahedra,  an edgeedge with one O(2)MgCo2Te trigonal pyramid, and  an edgeedge with one O(4)MgCo2Te trigonal pyramid. In the second O site, O(2) is bonded to one Mg(1), one Co(2), one Co(3), and one Te(1) atom to form distorted OMgCo2Te trigonal pyramids that share  a cornercorner with one O(6)MgCo3 tetrahedra,  a cornercorner with one O(1)MgCo2Te trigonal pyramid,  a cornercorner with one O(4)MgCo2Te trigonal pyramid,  an edgeedge with one O(6)MgCo3 tetrahedra,  an edgeedge with one O(1)MgCo2Te trigonal pyramid, and  an edgeedge with one O(4)MgCo2Te trigonal pyramid. In the third O site, O(3) is bonded in a distorted trigonal non-coplanar geometry to one Co(1), one Co(2), and one Co(3) atom. In the fourth O site, O(4) is bonded to one Mg(1), one Co(1), one Co(2), and one Te(1) atom to form distorted OMgCo2Te trigonal pyramids that share  a cornercorner with one O(6)MgCo3 tetrahedra,  a cornercorner with one O(1)MgCo2Te trigonal pyramid,  a cornercorner with one O(2)MgCo2Te trigonal pyramid,  an edgeedge with one O(6)MgCo3 tetrahedra,  an edgeedge with one O(1)MgCo2Te trigonal pyramid, and  an edgeedge with one O(2)MgCo2Te trigonal pyramid. In the fifth O site, O(5) is bonded in a distorted T-shaped geometry to one Co(1), one Co(2), and one Te(1) atom. In the sixth O site, O(6) is bonded to one Mg(1), one Co(1), one Co(2), and one Co(3) atom to form a mixture of corner and edge-sharing OMgCo3 tetrahedra. In the seventh O site, O(7) is bonded in a distorted T-shaped geometry to one Co(2), one Co(3), and one Te(1) atom. In the eighth O site, O(8) is bonded in a distorted T-shaped geometry to one Co(1), one Co(3), and one Te(1) atom.