ZnC7H4O5 crystallizes in the orthorhombic Pbam space group. Zn(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form corner-sharing ZnO6 octahedra. The corner-sharing octahedral tilt angles are 70°. Both Zn(1)-O(1) bond lengths are 2.07 Å. Both Zn(1)-O(2) bond lengths are 2.13 Å. There is one shorter (2.15 Å) and one longer (2.17 Å) Zn(1)-O(3) bond length. There are four inequivalent C sites. In the first C site, C(3) is bonded in a trigonal planar geometry to one C(3) and two equivalent C(2) atoms. The C(3)-C(3) bond length is 1.44 Å. Both C(3)-C(2) bond lengths are 1.43 Å. In the second C site, C(4) is bonded in a distorted bent 120 degrees geometry to one C(2), one O(1), and one O(2) atom. The C(4)-C(2) bond length is 1.50 Å. The C(4)-O(1) bond length is 1.27 Å. The C(4)-O(2) bond length is 1.28 Å. In the third C site, C(1) is bonded in a distorted single-bond geometry to one C(2) and one H(1) atom. The C(1)-C(2) bond length is 1.39 Å. The C(1)-H(1) bond length is 1.09 Å. In the fourth C site, C(2) is bonded in a trigonal planar geometry to one C(1), one C(3), and one C(4) atom. There are two inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one C(1) atom. In the second H site, H(2) is bonded in a distorted single-bond geometry to one O(2) and one O(3) atom. The H(2)-O(2) bond length is 1.67 Å. The H(2)-O(3) bond length is 1.01 Å. There are three inequivalent O sites. In the first O site, O(3) is bonded in a distorted water-like geometry to two equivalent Zn(1) and two equivalent H(2) atoms. In the second O site, O(1) is bonded in a distorted bent 150 degrees geometry to one Zn(1) and one C(4) atom. In the third O site, O(2) is bonded in a distorted trigonal non-coplanar geometry to one Zn(1), one C(4), and one H(2) atom. Linkers: 2 [O]C(=O)c1ccc(C([O])=O)c2c(C([O])=O)ccc(C([O])=O)c12. Metal clusters: 4 [Zn]. RCSR code: scu. The MOF has largest included sphere 1.90 A, density 2.27 g/cm3, surface area 2659.66 m2/g, accessible volume 0.08 cm3/g