ErC23H20(SO3)2(CH)4 crystallizes in the monoclinic P2_1/c space group. The structure consists of sixteen 02329_fluka molecules inside a ErC23H20(SO3)2 framework. In the ErC23H20(SO3)2 framework, Er(1) is bonded in a 7-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), and two equivalent O(6) atoms. The Er(1)-O(1) bond length is 2.52 Å. The Er(1)-O(2) bond length is 2.25 Å. The Er(1)-O(3) bond length is 2.33 Å. The Er(1)-O(4) bond length is 2.31 Å. The Er(1)-O(5) bond length is 2.30 Å. There is one shorter (2.32 Å) and one longer (2.52 Å) Er(1)-O(6) bond length. There are twenty-three inequivalent C sites. In the first C site, C(1) is bonded in a distorted bent 120 degrees geometry to one C(5), one O(2), and one O(5) atom. The C(1)-C(5) bond length is 1.51 Å. The C(1)-O(2) bond length is 1.26 Å. The C(1)-O(5) bond length is 1.25 Å. In the second C site, C(2) is bonded in a distorted single-bond geometry to one C(6) and one H(1) atom. The C(2)-C(6) bond length is 1.39 Å. The C(2)-H(1) bond length is 0.93 Å. In the third C site, C(3) is bonded in a trigonal planar geometry to one C(19), one C(6), and one S(1) atom. The C(3)-C(19) bond length is 1.40 Å. The C(3)-C(6) bond length is 1.41 Å. The C(3)-S(1) bond length is 1.76 Å. In the fourth C site, C(4) is bonded in a distorted single-bond geometry to one C(5) and one H(2) atom. The C(4)-C(5) bond length is 1.40 Å. The C(4)-H(2) bond length is 0.93 Å. In the fifth C site, C(5) is bonded in a trigonal planar geometry to one C(1), one C(10), and one C(4) atom. The C(5)-C(10) bond length is 1.40 Å. In the sixth C site, C(6) is bonded in a trigonal planar geometry to one C(2), one C(3), and one C(9) atom. The C(6)-C(9) bond length is 1.51 Å. In the seventh C site, C(9) is bonded in a distorted bent 120 degrees geometry to one C(6), one O(3), and one O(4) atom. The C(9)-O(3) bond length is 1.25 Å. The C(9)-O(4) bond length is 1.25 Å. In the eighth C site, C(10) is bonded in a trigonal planar geometry to one C(16), one C(5), and one S(2) atom. The C(10)-C(16) bond length is 1.39 Å. The C(10)-S(2) bond length is 1.79 Å. In the ninth C site, C(11) is bonded in a water-like geometry to one C(15); two equivalent H(5,6); and one S(2) atom. The C(11)-C(15) bond length is 1.51 Å. Both C(11)-H(5,6) bond lengths are 0.97 Å. The C(11)-S(2) bond length is 1.82 Å. In the tenth C site, C(12) is bonded in a trigonal non-coplanar geometry to one C(14); one H(7); and two equivalent H(8,9) atoms. The C(12)-C(14) bond length is 1.51 Å. The C(12)-H(7) bond length is 0.96 Å. Both C(12)-H(8,9) bond lengths are 0.96 Å. In the eleventh C site, C(13) is bonded in a trigonal planar geometry to one C(14), one C(17), and one C(22) atom. The C(13)-C(14) bond length is 1.40 Å. The C(13)-C(17) bond length is 1.51 Å. The C(13)-C(22) bond length is 1.39 Å. In the twelfth C site, C(14) is bonded in a trigonal planar geometry to one C(12), one C(13), and one C(24) atom. The C(14)-C(24) bond length is 1.40 Å. In the thirteenth C site, C(15) is bonded in a trigonal planar geometry to one C(11), one C(18), and one C(24) atom. The C(15)-C(18) bond length is 1.40 Å. The C(15)-C(24) bond length is 1.39 Å. In the fourteenth C site, C(16) is bonded in a distorted single-bond geometry to one C(10) and one H(10) atom. The C(16)-H(10) bond length is 0.93 Å. In the fifteenth C site, C(17) is bonded in a water-like geometry to one C(13); two equivalent H(11,12); and one S(1) atom. Both C(17)-H(11,12) bond lengths are 0.97 Å. The C(17)-S(1) bond length is 1.82 Å. In the sixteenth C site, C(18) is bonded in a trigonal planar geometry to one C(15), one C(22), and one C(26) atom. The C(18)-C(22) bond length is 1.40 Å. The C(18)-C(26) bond length is 1.51 Å. In the seventeenth C site, C(19) is bonded in a distorted single-bond geometry to one C(3) and one H(13) atom. The C(19)-H(13) bond length is 0.93 Å. In the eighteenth C site, C(22) is bonded in a trigonal planar geometry to one C(13), one C(18), and one C(23) atom. The C(22)-C(23) bond length is 1.52 Å. In the nineteenth C site, C(23) is bonded in a trigonal non-coplanar geometry to one C(22); one H(16); and two equivalent H(17,18) atoms. The C(23)-H(16) bond length is 0.96 Å. Both C(23)-H(17,18) bond lengths are 0.96 Å. In the twentieth C site, C(24) is bonded in a trigonal planar geometry to one C(14), one C(15), and one C(25) atom. The C(24)-C(25) bond length is 1.51 Å. In the twenty-first C site, C(25) is bonded in a trigonal non-coplanar geometry to one C(24); one H(19); and two equivalent H(20,21) atoms. The C(25)-H(19) bond length is 0.96 Å. Both C(25)-H(20,21) bond lengths are 0.96 Å. In the twenty-second C site, C(26) is bonded in a trigonal non-coplanar geometry to one C(18); one H(22); and two equivalent H(23,24) atoms. The C(26)-H(22) bond length is 0.96 Å. Both C(26)-H(23,24) bond lengths are 0.96 Å. In the twenty-third C site, C(27) is bonded in a bent 120 degrees geometry to one O(1) and one O(6) atom. The C(27)-O(1) bond length is 1.25 Å. The C(27)-O(6) bond length is 1.25 Å. There are fourteen inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one C(2) atom. In the second H site, H(2) is bonded in a single-bond geometry to one C(4) atom. In the third H site, H(5,6) is bonded in a single-bond geometry to one C(11) atom. In the fourth H site, H(7) is bonded in a single-bond geometry to one C(12) atom. In the fifth H site, H(8,9) is bonded in a single-bond geometry to one C(12) atom. In the sixth H site, H(10) is bonded in a single-bond geometry to one C(16) atom. In the seventh H site, H(11,12) is bonded in a single-bond geometry to one C(17) atom. In the eighth H site, H(13) is bonded in a single-bond geometry to one C(19) atom. In the ninth H site, H(16) is bonded in a single-bond geometry to one C(23) atom. In the tenth H site, H(17,18) is bonded in a single-bond geometry to one C(23) atom. In the eleventh H site, H(19) is bonded in a single-bond geometry to one C(25) atom. In the twelfth H site, H(20,21) is bonded in a single-bond geometry to one C(25) atom. In the thirteenth H site, H(22) is bonded in a single-bond geometry to one C(26) atom. In the fourteenth H site, H(23,24) is bonded in a single-bond geometry to one C(26) atom. There are two inequivalent S sites. In the first S site, S(1) is bonded in a water-like geometry to one C(17) and one C(3) atom. In the second S site, S(2) is bonded in a water-like geometry to one C(10) and one C(11) atom. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to one Er(1) and one C(27) atom. In the second O site, O(2) is bonded in a distorted bent 150 degrees geometry to one Er(1) and one C(1) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one Er(1) and one C(9) atom. In the fourth O site, O(4) is bonded in a distorted bent 150 degrees geometry to one Er(1) and one C(9) atom. In the fifth O site, O(5) is bonded in a distorted bent 150 degrees geometry to one Er(1) and one C(1) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to two equivalent Er(1) and one C(27) atom. Linkers: 4 Cc1c(C)c(CSc2ccccc2C([O])=O)c(C)c(C)c1CSc1ccccc1C([O])=O. Metal clusters: 4 [Er]. The MOF has largest included sphere 4.81 A, density 1.47 g/cm3, surface area 3903.84 m2/g, accessible volume 0.26 cm3/g