MgCo2(SO5)2 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), one O(3), one O(5), one O(6), one O(7), and one O(8) atom to form distorted MgO6 octahedra that share  a cornercorner with one Co(1)O6 octahedra,  a cornercorner with one S(1)O4 tetrahedra, corners with two equivalent S(2)O4 tetrahedra,  an edgeedge with one Co(1)O6 octahedra, edges with two equivalent Co(2)O6 octahedra, and  an edgeedge with one S(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 48°. There are two inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(1), one O(2), one O(4), one O(6), one O(7), and one O(9) atom to form distorted CoO6 octahedra that share  a cornercorner with one Mg(1)O6 octahedra, corners with two equivalent Co(2)O6 octahedra, corners with two equivalent S(1)O4 tetrahedra, corners with two equivalent S(2)O4 tetrahedra, and  an edgeedge with one Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 31-48°. In the second Co site, Co(2) is bonded to one O(1), one O(10), one O(2), one O(3), one O(5), and one O(8) atom to form distorted CoO6 octahedra that share corners with two equivalent Co(1)O6 octahedra, corners with two equivalent S(1)O4 tetrahedra, corners with two equivalent S(2)O4 tetrahedra, and edges with two equivalent Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 31-43°. There are two inequivalent S sites. In the first S site, S(1) is bonded to one O(3), one O(4), one O(7), and one O(8) atom to form SO4 tetrahedra that share  a cornercorner with one Mg(1)O6 octahedra, corners with two equivalent Co(1)O6 octahedra, corners with two equivalent Co(2)O6 octahedra, and  an edgeedge with one Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 29-55°. In the second S site, S(2) is bonded to one O(10), one O(5), one O(6), and one O(9) atom to form SO4 tetrahedra that share corners with two equivalent Mg(1)O6 octahedra, corners with two equivalent Co(1)O6 octahedra, and corners with two equivalent Co(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 24-52°. There are ten inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Mg(1), one Co(1), and one Co(2) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Co(1) and one Co(2) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Mg(1), one Co(2), and one S(1) atom. In the fourth O site, O(4) is bonded in a distorted bent 150 degrees geometry to one Co(1) and one S(1) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Mg(1), one Co(2), and one S(2) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Mg(1), one Co(1), and one S(2) atom. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one Mg(1), one Co(1), and one S(1) atom. In the eighth O site, O(8) is bonded in a distorted T-shaped geometry to one Mg(1), one Co(2), and one S(1) atom. In the ninth O site, O(9) is bonded in a distorted bent 120 degrees geometry to one Co(1) and one S(2) atom. In the tenth O site, O(10) is bonded in a bent 150 degrees geometry to one Co(2) and one S(2) atom.
MgCo2(SO5)2 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), one O(3), one O(5), one O(6), one O(7), and one O(8) atom to form distorted MgO6 octahedra that share  a cornercorner with one Co(1)O6 octahedra,  a cornercorner with one S(1)O4 tetrahedra, corners with two equivalent S(2)O4 tetrahedra,  an edgeedge with one Co(1)O6 octahedra, edges with two equivalent Co(2)O6 octahedra, and  an edgeedge with one S(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 48°. The Mg(1)-O(1) bond length is 1.98 Å. The Mg(1)-O(3) bond length is 2.13 Å. The Mg(1)-O(5) bond length is 2.21 Å. The Mg(1)-O(6) bond length is 2.33 Å. The Mg(1)-O(7) bond length is 2.17 Å. The Mg(1)-O(8) bond length is 2.14 Å. There are two inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(1), one O(2), one O(4), one O(6), one O(7), and one O(9) atom to form distorted CoO6 octahedra that share  a cornercorner with one Mg(1)O6 octahedra, corners with two equivalent Co(2)O6 octahedra, corners with two equivalent S(1)O4 tetrahedra, corners with two equivalent S(2)O4 tetrahedra, and  an edgeedge with one Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 31-48°. The Co(1)-O(1) bond length is 1.83 Å. The Co(1)-O(2) bond length is 1.80 Å. The Co(1)-O(4) bond length is 2.08 Å. The Co(1)-O(6) bond length is 2.30 Å. The Co(1)-O(7) bond length is 2.39 Å. The Co(1)-O(9) bond length is 2.06 Å. In the second Co site, Co(2) is bonded to one O(1), one O(10), one O(2), one O(3), one O(5), and one O(8) atom to form distorted CoO6 octahedra that share corners with two equivalent Co(1)O6 octahedra, corners with two equivalent S(1)O4 tetrahedra, corners with two equivalent S(2)O4 tetrahedra, and edges with two equivalent Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 31-43°. The Co(2)-O(1) bond length is 1.87 Å. The Co(2)-O(10) bond length is 2.05 Å. The Co(2)-O(2) bond length is 1.76 Å. The Co(2)-O(3) bond length is 2.24 Å. The Co(2)-O(5) bond length is 2.14 Å. The Co(2)-O(8) bond length is 2.33 Å. There are two inequivalent S sites. In the first S site, S(1) is bonded to one O(3), one O(4), one O(7), and one O(8) atom to form SO4 tetrahedra that share  a cornercorner with one Mg(1)O6 octahedra, corners with two equivalent Co(1)O6 octahedra, corners with two equivalent Co(2)O6 octahedra, and  an edgeedge with one Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 29-55°. The S(1)-O(3) bond length is 1.51 Å. The S(1)-O(4) bond length is 1.47 Å. The S(1)-O(7) bond length is 1.50 Å. The S(1)-O(8) bond length is 1.50 Å. In the second S site, S(2) is bonded to one O(10), one O(5), one O(6), and one O(9) atom to form SO4 tetrahedra that share corners with two equivalent Mg(1)O6 octahedra, corners with two equivalent Co(1)O6 octahedra, and corners with two equivalent Co(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 24-52°. The S(2)-O(10) bond length is 1.47 Å. The S(2)-O(5) bond length is 1.52 Å. The S(2)-O(6) bond length is 1.50 Å. The S(2)-O(9) bond length is 1.48 Å. There are ten inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Mg(1), one Co(1), and one Co(2) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Co(1) and one Co(2) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Mg(1), one Co(2), and one S(1) atom. In the fourth O site, O(4) is bonded in a distorted bent 150 degrees geometry to one Co(1) and one S(1) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Mg(1), one Co(2), and one S(2) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Mg(1), one Co(1), and one S(2) atom. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one Mg(1), one Co(1), and one S(1) atom. In the eighth O site, O(8) is bonded in a distorted T-shaped geometry to one Mg(1), one Co(2), and one S(1) atom. In the ninth O site, O(9) is bonded in a distorted bent 120 degrees geometry to one Co(1) and one S(2) atom. In the tenth O site, O(10) is bonded in a bent 150 degrees geometry to one Co(2) and one S(2) atom.