NiC7NH7O6 crystallizes in the triclinic P-1 space group. Ni(1) is bonded in an octahedral geometry to one N(1), one O(1), one O(2), one O(3), one O(5), and one O(6) atom. The Ni(1)-N(1) bond length is 2.01 Å. The Ni(1)-O(1) bond length is 2.18 Å. The Ni(1)-O(2) bond length is 2.11 Å. The Ni(1)-O(3) bond length is 2.02 Å. The Ni(1)-O(5) bond length is 2.10 Å. The Ni(1)-O(6) bond length is 2.06 Å. There are seven inequivalent C sites. In the first C site, C(1) is bonded in a distorted bent 120 degrees geometry to one C(2), one O(1), and one O(2) atom. The C(1)-C(2) bond length is 1.50 Å. The C(1)-O(1) bond length is 1.29 Å. The C(1)-O(2) bond length is 1.26 Å. In the second C site, C(2) is bonded in a trigonal planar geometry to one C(1), one C(3), and one C(4) atom. The C(2)-C(3) bond length is 1.40 Å. The C(2)-C(4) bond length is 1.40 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(5) atom. The C(3)-C(4) bond length is 1.40 Å. The C(3)-H(5) bond length is 1.09 Å. In the fourth C site, C(4) is bonded in a trigonal planar geometry to one C(2), one C(3), and one C(5) atom. The C(4)-C(5) bond length is 1.50 Å. In the fifth C site, C(5) is bonded in a distorted bent 120 degrees geometry to one C(4), one O(3), and one O(4) atom. The C(5)-O(3) bond length is 1.28 Å. The C(5)-O(4) bond length is 1.27 Å. In the sixth C site, C(6) is bonded in a distorted bent 120 degrees geometry to one N(1) and one H(6) atom. The C(6)-N(1) bond length is 1.35 Å. The C(6)-H(6) bond length is 1.09 Å. In the seventh C site, C(7) is bonded in a distorted bent 120 degrees geometry to one N(1) and one H(7) atom. The C(7)-N(1) bond length is 1.34 Å. The C(7)-H(7) bond length is 1.09 Å. N(1) is bonded in a trigonal planar geometry to one Ni(1), one C(6), and one C(7) atom. There are seven inequivalent H sites. In the first H site, H(1) is bonded in a distorted linear geometry to one O(4) and one O(5) atom. The H(1)-O(4) bond length is 1.57 Å. The H(1)-O(5) bond length is 1.03 Å. In the second H site, H(2) is bonded in a distorted single-bond geometry to one O(1) and one O(5) atom. The H(2)-O(1) bond length is 1.60 Å. The H(2)-O(5) bond length is 1.01 Å. In the third H site, H(3) is bonded in a single-bond geometry to one O(6) atom. The H(3)-O(6) bond length is 0.97 Å. In the fourth H site, H(4) is bonded in a distorted linear geometry to one O(5) and one O(6) atom. The H(4)-O(5) bond length is 1.63 Å. The H(4)-O(6) bond length is 1.01 Å. In the fifth H site, H(5) is bonded in a single-bond geometry to one C(3) atom. In the sixth H site, H(6) is bonded in a single-bond geometry to one C(6) atom. In the seventh H site, H(7) is bonded in a single-bond geometry to one C(7) atom. There are six inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Ni(1), one C(1), and one H(2) atom. In the second O site, O(2) is bonded in an L-shaped geometry to one Ni(1) and one C(1) atom. In the third O site, O(3) is bonded in a bent 120 degrees geometry to one Ni(1) and one C(5) atom. In the fourth O site, O(4) is bonded in a water-like geometry to one C(5) and one H(1) atom. In the fifth O site, O(5) is bonded in a distorted water-like geometry to one Ni(1), one H(1), one H(2), and one H(4) atom. In the sixth O site, O(6) is bonded in a distorted trigonal non-coplanar geometry to one Ni(1), one H(3), and one H(4) atom. Linkers: 1 c1cnccn1 ,1 [O]C(=O)c1cc(C([O])=O)c(C([O])=O)cc1C([O])=O. Metal clusters: 2 O.O.O=[C]O[Ni]1O[C]O1. The MOF has largest included sphere 2.33 A, density 1.90 g/cm3, surface area 3690.15 m2/g, accessible volume 0.09 cm3/g