MgC6SO4 crystallizes in the monoclinic C2 space group. There are three inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 5-coordinate geometry to one O(11), one O(12), one O(3), one O(4), and one O(9) atom. The Mg(1)-O(11) bond length is 2.15 Å. The Mg(1)-O(12) bond length is 2.04 Å. The Mg(1)-O(3) bond length is 2.38 Å. The Mg(1)-O(4) bond length is 2.01 Å. The Mg(1)-O(9) bond length is 2.06 Å. In the second Mg site, Mg(2) is bonded in a 5-coordinate geometry to one O(2), one O(3), one O(5), one O(7), and one O(8) atom. The Mg(2)-O(2) bond length is 2.07 Å. The Mg(2)-O(3) bond length is 2.00 Å. The Mg(2)-O(5) bond length is 2.05 Å. The Mg(2)-O(7) bond length is 2.30 Å. The Mg(2)-O(8) bond length is 2.10 Å. In the third Mg site, Mg(3) is bonded in a 5-coordinate geometry to one O(1), one O(10), one O(12), one O(6), and one O(7) atom. The Mg(3)-O(1) bond length is 2.03 Å. The Mg(3)-O(10) bond length is 2.15 Å. The Mg(3)-O(12) bond length is 2.33 Å. The Mg(3)-O(6) bond length is 2.03 Å. The Mg(3)-O(7) bond length is 2.08 Å. There are eighteen inequivalent C sites. In the first C site, C(1) is bonded in a bent 120 degrees geometry to one C(7) and one C(8) atom. The C(1)-C(7) bond length is 1.49 Å. The C(1)-C(8) bond length is 1.35 Å. In the second C site, C(2) is bonded in a bent 120 degrees geometry to one C(13) and one C(17) atom. The C(2)-C(13) bond length is 1.41 Å. The C(2)-C(17) bond length is 1.39 Å. In the third C site, C(3) is bonded in a bent 120 degrees geometry to one C(3) and one C(5) atom. The C(3)-C(3) bond length is 1.41 Å. The C(3)-C(5) bond length is 1.36 Å. In the fourth C site, C(4) is bonded in a water-like geometry to one C(10) and one C(4) atom. The C(4)-C(10) bond length is 1.37 Å. The C(4)-C(4) bond length is 1.43 Å. In the fifth C site, C(5) is bonded in a trigonal planar geometry to one C(3), one C(9), and one S(3) atom. The C(5)-C(9) bond length is 1.50 Å. The C(5)-S(3) bond length is 1.71 Å. In the sixth C site, C(6) is bonded in a trigonal planar geometry to one C(11), one C(7), and one S(1) atom. The C(6)-C(11) bond length is 1.48 Å. The C(6)-C(7) bond length is 1.34 Å. The C(6)-S(1) bond length is 1.74 Å. In the seventh C site, C(7) is bonded in a water-like geometry to one C(1) and one C(6) atom. In the eighth C site, C(8) is bonded in a trigonal planar geometry to one C(1), one C(14), and one S(1) atom. The C(8)-C(14) bond length is 1.48 Å. The C(8)-S(1) bond length is 1.71 Å. In the ninth C site, C(9) is bonded in a distorted bent 120 degrees geometry to one C(5), one O(1), and one O(5) atom. The C(9)-O(1) bond length is 1.24 Å. The C(9)-O(5) bond length is 1.25 Å. In the tenth C site, C(10) is bonded in a trigonal planar geometry to one C(12), one C(4), and one S(4) atom. The C(10)-C(12) bond length is 1.50 Å. The C(10)-S(4) bond length is 1.69 Å. In the eleventh C site, C(11) is bonded in a distorted bent 120 degrees geometry to one C(6), one O(6), and one O(9) atom. The C(11)-O(6) bond length is 1.26 Å. The C(11)-O(9) bond length is 1.24 Å. In the twelfth C site, C(12) is bonded in a bent 120 degrees geometry to one C(10), one O(7), and one O(8) atom. The C(12)-O(7) bond length is 1.26 Å. The C(12)-O(8) bond length is 1.24 Å. In the thirteenth C site, C(13) is bonded in a bent 120 degrees geometry to one C(18) and one C(2) atom. The C(13)-C(18) bond length is 1.35 Å. In the fourteenth C site, C(14) is bonded in a distorted bent 120 degrees geometry to one C(8), one O(2), and one O(4) atom. The C(14)-O(2) bond length is 1.25 Å. The C(14)-O(4) bond length is 1.24 Å. In the fifteenth C site, C(15) is bonded in a bent 120 degrees geometry to one C(18), one O(10), and one O(12) atom. The C(15)-C(18) bond length is 1.47 Å. The C(15)-O(10) bond length is 1.27 Å. The C(15)-O(12) bond length is 1.25 Å. In the sixteenth C site, C(16) is bonded in a bent 120 degrees geometry to one C(17), one O(11), and one O(3) atom. The C(16)-C(17) bond length is 1.46 Å. The C(16)-O(11) bond length is 1.24 Å. The C(16)-O(3) bond length is 1.27 Å. In the seventeenth C site, C(17) is bonded in a trigonal planar geometry to one C(16), one C(2), and one S(2) atom. The C(17)-S(2) bond length is 1.71 Å. In the eighteenth C site, C(18) is bonded in a trigonal planar geometry to one C(13), one C(15), and one S(2) atom. The C(18)-S(2) bond length is 1.72 Å. There are four inequivalent S sites. In the first S site, S(1) is bonded in an L-shaped geometry to one C(6) and one C(8) atom. In the second S site, S(2) is bonded in an L-shaped geometry to one C(17) and one C(18) atom. In the third S site, S(3) is bonded in an L-shaped geometry to two equivalent C(5) atoms. In the fourth S site, S(4) is bonded in an L-shaped geometry to two equivalent C(10) atoms. There are twelve inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 150 degrees geometry to one Mg(3) and one C(9) atom. In the second O site, O(2) is bonded in a distorted bent 150 degrees geometry to one Mg(2) and one C(14) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Mg(1), one Mg(2), and one C(16) atom. In the fourth O site, O(4) is bonded in a distorted single-bond geometry to one Mg(1) and one C(14) atom. In the fifth O site, O(5) is bonded in a distorted single-bond geometry to one Mg(2) and one C(9) atom. In the sixth O site, O(6) is bonded in a bent 120 degrees geometry to one Mg(3) and one C(11) atom. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one Mg(2), one Mg(3), and one C(12) atom. In the eighth O site, O(8) is bonded in a distorted L-shaped geometry to one Mg(2) and one C(12) atom. In the ninth O site, O(9) is bonded in a distorted bent 150 degrees geometry to one Mg(1) and one C(11) atom. In the tenth O site, O(10) is bonded in a distorted single-bond geometry to one Mg(3) and one C(15) atom. In the eleventh O site, O(11) is bonded in a distorted L-shaped geometry to one Mg(1) and one C(16) atom. In the twelfth O site, O(12) is bonded in a 3-coordinate geometry to one Mg(1), one Mg(3), and one C(15) atom. Linkers: 13 [O]C(=O)c1[c][c]c(C([O])=O)s1. Metal clusters: 4 O=[C]O[Mg]O[C]=O.O=[C]O[Mg]O[C]O[Mg]O[C]=O.[O][C]=O. RCSR code: acs. The MOF has largest included sphere 7.12 A, density 0.80 g/cm3, surface area 4265.98 m2/g, accessible volume 0.83 cm3/g