Mg3C12H14(SO7)2 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(7) atoms to form corner-sharing MgO6 octahedra. The corner-sharing octahedral tilt angles range from 59-60°. Both Mg(1)-O(1) bond lengths are 2.08 Å. Both Mg(1)-O(2) bond lengths are 2.05 Å. Both Mg(1)-O(7) bond lengths are 2.12 Å. In the second Mg site, Mg(2) is bonded to one O(3), one O(4), one O(5), one O(6), and two equivalent O(2) atoms to form a mixture of edge and corner-sharing MgO6 octahedra. The corner-sharing octahedral tilt angles range from 59-60°. The Mg(2)-O(3) bond length is 2.11 Å. The Mg(2)-O(4) bond length is 2.20 Å. The Mg(2)-O(5) bond length is 2.07 Å. The Mg(2)-O(6) bond length is 2.10 Å. Both Mg(2)-O(2) bond lengths are 2.06 Å. There are six inequivalent C sites. In the first C site, C(1) is bonded in a distorted bent 120 degrees geometry to one C(2), one O(6), and one O(7) atom. The C(1)-C(2) bond length is 1.48 Å. The C(1)-O(6) bond length is 1.27 Å. The C(1)-O(7) bond length is 1.28 Å. In the second C site, C(2) is bonded in a trigonal planar geometry to one C(1), one C(6), and one S(1) atom. The C(2)-C(6) bond length is 1.39 Å. The C(2)-S(1) bond length is 1.72 Å. In the third C site, C(3) is bonded in a trigonal planar geometry to one C(4), one C(5), and one S(1) atom. The C(3)-C(4) bond length is 1.48 Å. The C(3)-C(5) bond length is 1.39 Å. The C(3)-S(1) bond length is 1.72 Å. In the fourth C site, C(4) is bonded in a distorted bent 120 degrees geometry to one C(3), one O(1), and one O(3) atom. The C(4)-O(1) bond length is 1.28 Å. The C(4)-O(3) bond length is 1.27 Å. In the fifth C site, C(5) is bonded in a distorted single-bond geometry to one C(3), one C(6), and one H(6) atom. The C(5)-C(6) bond length is 1.41 Å. The C(5)-H(6) bond length is 1.09 Å. In the sixth C site, C(6) is bonded in a distorted single-bond geometry to one C(2), one C(5), and one H(7) atom. The C(6)-H(7) bond length is 1.09 Å. There are seven inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one O(2) atom. The H(1)-O(2) bond length is 0.97 Å. In the second H site, H(2) is bonded in a single-bond geometry to one O(4) and one O(7) atom. The H(2)-O(4) bond length is 1.01 Å. The H(2)-O(7) bond length is 1.70 Å. In the third H site, H(3) is bonded in a single-bond geometry to one O(4) atom. The H(3)-O(4) bond length is 0.97 Å. In the fourth H site, H(4) is bonded in a single-bond geometry to one O(5) atom. The H(4)-O(5) bond length is 0.99 Å. In the fifth H site, H(5) is bonded in a single-bond geometry to one O(1) and one O(5) atom. The H(5)-O(1) bond length is 1.71 Å. The H(5)-O(5) bond length is 0.99 Å. In the sixth H site, H(6) is bonded in a single-bond geometry to one C(5) atom. In the seventh H site, H(7) is bonded in a single-bond geometry to one C(6) atom. S(1) is bonded in an L-shaped geometry to one C(2) and one C(3) atom. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Mg(1), one C(4), and one H(5) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to one Mg(1), two equivalent Mg(2), and one H(1) atom. In the third O site, O(3) is bonded in a bent 120 degrees geometry to one Mg(2) and one C(4) atom. In the fourth O site, O(4) is bonded in a distorted water-like geometry to one Mg(2), one H(2), and one H(3) atom. In the fifth O site, O(5) is bonded in a distorted trigonal non-coplanar geometry to one Mg(2), one H(4), and one H(5) atom. In the sixth O site, O(6) is bonded in a bent 120 degrees geometry to one Mg(2) and one C(1) atom. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one Mg(1), one C(1), and one H(2) atom. Linkers: 4 [O]C(=O)c1ccc(C([O])=O)s1. Metal clusters: 6 [Mg]. The MOF has largest included sphere 2.18 A, density 1.77 g/cm3, surface area 3671.80 m2/g, accessible volume 0.12 cm3/g