K2C5H5S2O9CH crystallizes in the monoclinic P2_1/c space group. The structure consists of four 02329_fluka molecules inside a K2C5H5S2O9 framework. In the K2C5H5S2O9 framework, there are two inequivalent K sites. In the first K site, K(1) is bonded in a 7-coordinate geometry to one O(1), one O(2), one O(5), one O(6), one O(8), and two equivalent O(3) atoms. The K(1)-O(1) bond length is 2.97 Å. The K(1)-O(2) bond length is 2.84 Å. The K(1)-O(5) bond length is 2.78 Å. The K(1)-O(6) bond length is 3.02 Å. The K(1)-O(8) bond length is 2.74 Å. There is one shorter (2.69 Å) and one longer (2.76 Å) K(1)-O(3) bond length. In the second K site, K(2) is bonded in a 7-coordinate geometry to one O(1), one O(2), one O(4), one O(5), one O(6), one O(7), and one O(9) atom. The K(2)-O(1) bond length is 2.74 Å. The K(2)-O(2) bond length is 2.69 Å. The K(2)-O(4) bond length is 2.83 Å. The K(2)-O(5) bond length is 3.03 Å. The K(2)-O(6) bond length is 2.81 Å. The K(2)-O(7) bond length is 2.81 Å. The K(2)-O(9) bond length is 2.68 Å. There are five inequivalent C sites. In the first C site, C(1) is bonded in a trigonal planar geometry to one C(2), one C(6), and one S(2) atom. The C(1)-C(2) bond length is 1.42 Å. The C(1)-C(6) bond length is 1.40 Å. The C(1)-S(2) bond length is 1.77 Å. In the second C site, C(2) is bonded in a distorted single-bond geometry to one C(1) and one O(7) atom. The C(2)-O(7) bond length is 1.35 Å. In the third C site, C(4) is bonded in a distorted single-bond geometry to one C(5) and one O(8) atom. The C(4)-C(5) bond length is 1.42 Å. The C(4)-O(8) bond length is 1.35 Å. In the fourth C site, C(5) is bonded in a trigonal planar geometry to one C(4), one C(6), and one S(1) atom. The C(5)-C(6) bond length is 1.39 Å. The C(5)-S(1) bond length is 1.78 Å. In the fifth C site, C(6) is bonded in a distorted single-bond geometry to one C(1), one C(5), and one H(6) atom. The C(6)-H(6) bond length is 1.09 Å. There are five inequivalent H sites. In the first H site, H(1) is bonded in a distorted bent 150 degrees geometry to one O(1) and one O(7) atom. The H(1)-O(1) bond length is 1.64 Å. The H(1)-O(7) bond length is 1.00 Å. In the second H site, H(2) is bonded in a distorted bent 150 degrees geometry to one O(4) and one O(8) atom. The H(2)-O(4) bond length is 1.65 Å. The H(2)-O(8) bond length is 1.01 Å. In the third H site, H(3) is bonded in a single-bond geometry to one O(9) atom. The H(3)-O(9) bond length is 0.98 Å. In the fourth H site, H(4) is bonded in a single-bond geometry to one O(9) atom. The H(4)-O(9) bond length is 0.99 Å. In the fifth H site, H(6) is bonded in a single-bond geometry to one C(6) atom. There are two inequivalent S sites. In the first S site, S(1) is bonded in a distorted trigonal non-coplanar geometry to one C(5), one O(4), one O(5), and one O(6) atom. The S(1)-O(4) bond length is 1.49 Å. The S(1)-O(5) bond length is 1.46 Å. The S(1)-O(6) bond length is 1.48 Å. In the second S site, S(2) is bonded in a distorted trigonal non-coplanar geometry to one C(1), one O(1), one O(2), and one O(3) atom. The S(2)-O(1) bond length is 1.49 Å. The S(2)-O(2) bond length is 1.48 Å. The S(2)-O(3) bond length is 1.46 Å. There are nine inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one K(1), one K(2), one H(1), and one S(2) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to one K(1), one K(2), and one S(2) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to two equivalent K(1) and one S(2) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one K(2), one H(2), and one S(1) atom. In the fifth O site, O(5) is bonded in a distorted single-bond geometry to one K(1), one K(2), and one S(1) atom. In the sixth O site, O(6) is bonded in a distorted single-bond geometry to one K(1), one K(2), and one S(1) atom. In the seventh O site, O(7) is bonded in a distorted water-like geometry to one K(2), one C(2), and one H(1) atom. In the eighth O site, O(8) is bonded in a distorted water-like geometry to one K(1), one C(4), and one H(2) atom. In the ninth O site, O(9) is bonded in a distorted water-like geometry to one K(2), one H(3), and one H(4) atom. Linkers: 4 [O]S([O])([O])c1cc(S([O])([O])[O])c(O)cc1O. Metal clusters: 8 [K]. The MOF has largest included sphere 1.80 A, density 1.99 g/cm3, surface area 1791.64 m2/g, accessible volume 0.04 cm3/g