KPrC14H6(SO5)2 crystallizes in the trigonal R3c space group. K(1) is bonded in a 5-coordinate geometry to one O(2), one O(3), one O(4), one O(5), and one O(8) atom. The K(1)-O(2) bond length is 2.58 Å. The K(1)-O(3) bond length is 2.73 Å. The K(1)-O(4) bond length is 2.70 Å. The K(1)-O(5) bond length is 2.90 Å. The K(1)-O(8) bond length is 2.85 Å. Pr(1) is bonded in a 8-coordinate geometry to one O(2), one O(3), one O(6), one O(9), two equivalent O(1), and two equivalent O(7) atoms. The Pr(1)-O(2) bond length is 2.52 Å. The Pr(1)-O(3) bond length is 2.47 Å. The Pr(1)-O(6) bond length is 2.56 Å. The Pr(1)-O(9) bond length is 2.44 Å. There is one shorter (2.44 Å) and one longer (2.67 Å) Pr(1)-O(1) bond length. There is one shorter (2.49 Å) and one longer (2.67 Å) Pr(1)-O(7) bond length. There are fourteen 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 C(7) atom. The C(1)-C(2) bond length is 1.39 Å. The C(1)-C(6) bond length is 1.39 Å. The C(1)-C(7) bond length is 1.50 Å. In the second C site, C(2) is bonded in a trigonal planar geometry to one C(1), one C(3), and one S(1) atom. The C(2)-C(3) bond length is 1.38 Å. The C(2)-S(1) bond length is 1.78 Å. In the third C site, C(3) is bonded in a distorted single-bond geometry to one C(2), one C(4), and one H(1) atom. The C(3)-C(4) bond length is 1.41 Å. The C(3)-H(1) bond length is 0.93 Å. In the fourth C site, C(4) is bonded in a trigonal planar geometry to one C(3), one C(5), and one C(8) atom. The C(4)-C(5) bond length is 1.38 Å. The C(4)-C(8) bond length is 1.48 Å. In the fifth C site, C(5) is bonded in a distorted single-bond geometry to one C(4) and one H(2) atom. The C(5)-H(2) bond length is 0.93 Å. In the sixth C site, C(6) is bonded in a distorted single-bond geometry to one C(1) and one H(3) atom. The C(6)-H(3) bond length is 0.93 Å. In the seventh C site, C(7) is bonded in a bent 120 degrees geometry to one C(1), one O(1), and one O(2) atom. The C(7)-O(1) bond length is 1.26 Å. The C(7)-O(2) bond length is 1.26 Å. In the eighth C site, C(8) is bonded in a trigonal planar geometry to one C(13), one C(4), and one C(9) atom. The C(8)-C(13) bond length is 1.40 Å. The C(8)-C(9) bond length is 1.39 Å. In the ninth C site, C(10) is bonded in a distorted single-bond geometry to one C(11) and one H(5) atom. The C(10)-C(11) bond length is 1.36 Å. The C(10)-H(5) bond length is 0.93 Å. In the tenth C site, C(11) is bonded in a trigonal planar geometry to one C(10), one C(12), and one C(14) atom. The C(11)-C(12) bond length is 1.43 Å. The C(11)-C(14) bond length is 1.50 Å. In the eleventh C site, C(9) is bonded in a distorted single-bond geometry to one C(8) and one H(4) atom. The C(9)-H(4) bond length is 0.93 Å. In the twelfth C site, C(12) is bonded in a trigonal planar geometry to one C(11), one C(13), and one S(2) atom. The C(12)-C(13) bond length is 1.37 Å. The C(12)-S(2) bond length is 1.79 Å. In the thirteenth C site, C(13) is bonded in a single-bond geometry to one C(12), one C(8), and one H(6) atom. The C(13)-H(6) bond length is 0.93 Å. In the fourteenth C site, C(14) is bonded in a distorted bent 120 degrees geometry to one C(11), one O(6), and one O(7) atom. The C(14)-O(6) bond length is 1.25 Å. The C(14)-O(7) bond length is 1.28 Å. There are six inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one C(3) atom. In the second H site, H(2) is bonded in a single-bond geometry to one C(5) atom. In the third H site, H(3) is bonded in a single-bond geometry to one C(6) atom. In the fourth H site, H(4) is bonded in a single-bond geometry to one C(9) atom. In the fifth H site, H(5) is bonded in a single-bond geometry to one C(10) atom. In the sixth H site, H(6) is bonded in a single-bond geometry to one C(13) 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(2), one O(3), one O(4), and one O(5) atom. The S(1)-O(3) bond length is 1.47 Å. The S(1)-O(4) bond length is 1.48 Å. The S(1)-O(5) bond length is 1.43 Å. In the second S site, S(2) is bonded in a distorted trigonal non-coplanar geometry to one C(12), one O(10), one O(8), and one O(9) atom. The S(2)-O(10) bond length is 1.42 Å. The S(2)-O(8) bond length is 1.45 Å. The S(2)-O(9) bond length is 1.45 Å. There are ten inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to two equivalent Pr(1) and one C(7) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to one K(1), one Pr(1), and one C(7) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one K(1), one Pr(1), and one S(1) atom. In the fourth O site, O(4) is bonded in a single-bond geometry to one K(1) and one S(1) atom. In the fifth O site, O(5) is bonded in a single-bond geometry to one K(1) and one S(1) atom. In the sixth O site, O(6) is bonded in a distorted single-bond geometry to one Pr(1) and one C(14) atom. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to two equivalent Pr(1) and one C(14) atom. In the eighth O site, O(8) is bonded in a distorted single-bond geometry to one K(1) and one S(2) atom. In the ninth O site, O(9) is bonded in a distorted single-bond geometry to one Pr(1) and one S(2) atom. In the tenth O site, O(10) is bonded in a single-bond geometry to one S(2) atom. Linkers: 18 [O]C(=O)c1ccc(-c2ccc(C([O])=O)c(S([O])([O])[O])c2)cc1S([O])([O])[O]. Metal clusters: 18 [K] ,18 [Pr]. The MOF has largest included sphere 15.92 A, density 0.98 g/cm3, surface area 2690.53 m2/g, accessible volume 0.59 cm3/g