Co2C17H9O9 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(1), one O(4), one O(5), one O(7), one O(8), and one O(9) atom to form distorted corner-sharing CoO6 octahedra. The Co(1)-O(1) bond length is 2.05 Å. The Co(1)-O(4) bond length is 2.09 Å. The Co(1)-O(5) bond length is 2.12 Å. The Co(1)-O(7) bond length is 2.11 Å. The Co(1)-O(8) bond length is 2.31 Å. The Co(1)-O(9) bond length is 2.01 Å. In the second Co site, Co(2) is bonded to one O(2), one O(3), one O(6), and two equivalent O(9) atoms to form CoO5 square pyramids that share corners with two equivalent Co(1)O6 octahedra and  an edgeedge with one Co(2)O5 square pyramid. The corner-sharing octahedral tilt angles range from 59-67°. The Co(2)-O(2) bond length is 2.05 Å. The Co(2)-O(3) bond length is 2.06 Å. The Co(2)-O(6) bond length is 2.11 Å. There is one shorter (2.05 Å) and one longer (2.13 Å) Co(2)-O(9) bond length. There are seventeen inequivalent C sites. In the first C site, C(1) is bonded in a trigonal planar geometry to one C(14), one C(2), and one C(6) atom. The C(1)-C(14) bond length is 1.51 Å. The C(1)-C(2) bond length is 1.39 Å. The C(1)-C(6) bond length is 1.40 Å. In the second C site, C(2) is bonded in a distorted single-bond geometry to one C(1), one C(3), and one H(1) atom. The C(2)-C(3) bond length is 1.39 Å. The C(2)-H(1) bond length is 0.95 Å. In the third C site, C(3) is bonded in a trigonal planar geometry to one C(15), one C(2), and one C(4) atom. The C(3)-C(15) bond length is 1.51 Å. The C(3)-C(4) bond length is 1.39 Å. In the fourth C site, C(4) is bonded in a distorted single-bond geometry to one C(3), 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 0.95 Å. In the fifth C site, C(5) is bonded in a trigonal planar geometry to one C(4), one C(6), and one C(7) atom. The C(5)-C(6) bond length is 1.38 Å. The C(5)-C(7) bond length is 1.51 Å. In the sixth C site, C(6) is bonded in a distorted single-bond geometry to one C(1), one C(5), and one H(3) atom. The C(6)-H(3) bond length is 0.95 Å. In the seventh C site, C(7) is bonded in a water-like geometry to one C(5), one C(8), one H(7), and one H(8) atom. The C(7)-C(8) bond length is 1.52 Å. The C(7)-H(7) bond length is 0.97 Å. The C(7)-H(8) bond length is 0.97 Å. In the eighth C site, C(8) is bonded in a trigonal planar geometry to one C(13), one C(7), 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(9) is bonded in a distorted single-bond geometry to one C(10), one C(8), and one H(4) atom. The C(9)-C(10) bond length is 1.40 Å. The C(9)-H(4) bond length is 0.95 Å. In the tenth C site, C(10) is bonded in a trigonal planar geometry to one C(11), one C(16), and one C(9) atom. The C(10)-C(11) bond length is 1.39 Å. The C(10)-C(16) bond length is 1.51 Å. In the eleventh C site, C(11) is bonded in a distorted single-bond geometry to one C(10), one C(12), and one H(5) atom. The C(11)-C(12) bond length is 1.39 Å. The C(11)-H(5) bond length is 0.95 Å. In the twelfth C site, C(12) is bonded in a trigonal planar geometry to one C(11), one C(13), and one C(17) atom. The C(12)-C(13) bond length is 1.39 Å. The C(12)-C(17) bond length is 1.50 Å. In the thirteenth C site, C(13) is bonded in a distorted single-bond geometry to one C(12), one C(8), and one H(6) atom. The C(13)-H(6) bond length is 0.95 Å. In the fourteenth C site, C(14) is bonded in a distorted bent 120 degrees geometry to one C(1), one O(1), and one O(2) atom. The C(14)-O(1) bond length is 1.26 Å. The C(14)-O(2) bond length is 1.26 Å. In the fifteenth C site, C(15) is bonded in a distorted bent 120 degrees geometry to one C(3), one O(3), and one O(4) atom. The C(15)-O(3) bond length is 1.27 Å. The C(15)-O(4) bond length is 1.25 Å. In the sixteenth C site, C(16) is bonded in a distorted bent 120 degrees geometry to one C(10), one O(5), and one O(6) atom. The C(16)-O(5) bond length is 1.27 Å. The C(16)-O(6) bond length is 1.25 Å. In the seventeenth C site, C(17) is bonded in a bent 120 degrees geometry to one C(12), one O(7), and one O(8) atom. The C(17)-O(7) bond length is 1.28 Å. The C(17)-O(8) bond length is 1.25 Å. There are nine 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(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(11) atom. In the sixth H site, H(6) is bonded in a single-bond geometry to one C(13) atom. In the seventh H site, H(7) is bonded in a single-bond geometry to one C(7) atom. In the eighth H site, H(8) is bonded in a single-bond geometry to one C(7) atom. In the ninth H site, H(9) is bonded in a single-bond geometry to one O(9) atom. The H(9)-O(9) bond length is 0.76 Å. There are nine inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 150 degrees geometry to one Co(1) and one C(14) atom. In the second O site, O(2) is bonded in a bent 120 degrees geometry to one Co(2) and one C(14) atom. In the third O site, O(3) is bonded in a bent 120 degrees geometry to one Co(2) and one C(15) atom. In the fourth O site, O(4) is bonded in a distorted bent 150 degrees geometry to one Co(1) and one C(15) atom. In the fifth O site, O(5) is bonded in a bent 120 degrees geometry to one Co(1) and one C(16) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one Co(2) and one C(16) atom. In the seventh O site, O(7) is bonded in an L-shaped geometry to one Co(1) and one C(17) atom. In the eighth O site, O(8) is bonded in a distorted single-bond geometry to one Co(1) and one C(17) atom. In the ninth O site, O(9) is bonded in a distorted single-bond geometry to one Co(1), two equivalent Co(2), and one H(9) atom. Linkers: 4 [O]C(=O)c1cc(Cc2cc(C([O])=O)cc(C([O])=O)c2)cc(C([O])=O)c1. Metal clusters: 2 O[Co]123(O[C]O[Co](O[C]O1)O[C]O[Co]14(O)(O[C]O[Co](O[C]O1)O[C]O2)O[C]O4)O[C]O3. The MOF has largest included sphere 4.76 A, density 1.26 g/cm3, surface area 3577.97 m2/g, accessible volume 0.42 cm3/g