Co2C9H7(NO)4 crystallizes in the tetragonal I4/m space group. Co(1) is bonded to one N(1), one N(2), one O(1), one O(2), and one O(3) atom to form distorted edge-sharing CoN2O3 square pyramids. The Co(1)-N(1) bond length is 2.20 Å. The Co(1)-N(2) bond length is 2.16 Å. The Co(1)-O(1) bond length is 2.05 Å. The Co(1)-O(2) bond length is 2.04 Å. The Co(1)-O(3) bond length is 2.10 Å. There are five inequivalent C sites. In the first C site, C(1) is bonded in a distorted bent 120 degrees geometry to one N(1) and one H(3) atom. The C(1)-N(1) bond length is 1.35 Å. The C(1)-H(3) bond length is 0.96 Å. In the second C site, C(2) is bonded in a distorted single-bond geometry to one C(3) and one H(1) atom. The C(2)-C(3) bond length is 1.34 Å. The C(2)-H(1) bond length is 0.95 Å. In the third C site, C(3) is bonded in a distorted trigonal planar geometry to one C(2), one N(2), and one H(2) atom. The C(3)-N(2) bond length is 1.34 Å. The C(3)-H(2) bond length is 0.97 Å. In the fourth C site, C(4) is bonded in a distorted trigonal planar geometry to one C(4), one N(1), and one N(2) atom. The C(4)-C(4) bond length is 1.47 Å. The C(4)-N(1) bond length is 1.31 Å. The C(4)-N(2) bond length is 1.34 Å. In the fifth C site, C(5) is bonded in a trigonal planar geometry to one O(3) and two equivalent O(1) atoms. The C(5)-O(3) bond length is 1.30 Å. Both C(5)-O(1) bond lengths are 1.27 Å. There are two inequivalent N sites. In the first N site, N(1) is bonded in a trigonal planar geometry to one Co(1), one C(1), and one C(4) atom. In the second N site, N(2) is bonded in a trigonal planar geometry to one Co(1), one C(3), and one C(4) atom. There are four inequivalent H sites. In the first H site, H(4) is bonded in a single-bond geometry to one O(2) atom. The H(4)-O(2) bond length is 0.85 Å. In the second H site, H(1) is bonded in a single-bond geometry to one C(2) atom. In the third H site, H(2) is bonded in a single-bond geometry to one C(3) atom. In the fourth H site, H(3) is bonded in a single-bond geometry to one C(1) atom. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 120 degrees geometry to one Co(1) and one C(5) atom. In the second O site, O(2) is bonded in a distorted trigonal non-coplanar geometry to two equivalent Co(1) and one H(4) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to two equivalent Co(1) and one C(5) atom. Linkers: 8 c1cnc(-c2ncccn2)nc1. Metal clusters: 1 O[Co]1O[C](O[Co])O[Co](O)O[C](O[Co])O[Co](O)O[C](O[Co])O[Co](O)O[C](O[Co])O1 ,1 O[Co]O[C]1O[Co]O[C](O[Co])O[Co](O)O[C](O[Co])O[Co](O)O[C](O[Co])O[Co](O)O1. The MOF has largest included sphere 9.34 A, density 1.22 g/cm3, surface area 3504.13 m2/g, accessible volume 0.48 cm3/g