ZnH4(C2O)3 crystallizes in the monoclinic P2_1/c space group. Zn(1) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form distorted corner-sharing ZnO4 trigonal pyramids. The Zn(1)-O(1) bond length is 2.11 Å. The Zn(1)-O(2) bond length is 2.00 Å. There is one shorter (1.92 Å) and one longer (1.93 Å) Zn(1)-O(3) bond length. There are six inequivalent C sites. In the first C site, C(4) is bonded in a distorted single-bond geometry to one C(3), one C(5), and one H(3) atom. The C(4)-C(3) bond length is 1.38 Å. The C(4)-C(5) bond length is 1.42 Å. The C(4)-H(3) bond length is 1.09 Å. In the second C site, C(5) is bonded in a trigonal planar geometry to one C(1), one C(4), and one C(5) atom. The C(5)-C(1) bond length is 1.42 Å. The C(5)-C(5) bond length is 1.44 Å. In the third C site, C(6) is bonded in a distorted bent 120 degrees geometry to one C(2), one O(1), and one O(2) atom. The C(6)-C(2) bond length is 1.49 Å. The C(6)-O(1) bond length is 1.27 Å. The C(6)-O(2) bond length is 1.29 Å. In the fourth C site, C(1) is bonded in a distorted trigonal planar geometry to one C(2), one C(5), 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 fifth C site, C(2) is bonded in a trigonal planar geometry to one C(1), one C(3), and one C(6) atom. The C(2)-C(3) bond length is 1.42 Å. In the sixth C site, C(3) is bonded in a distorted trigonal planar geometry to one C(2), one C(4), and one H(2) atom. The C(3)-H(2) bond length is 1.09 Å. There are four 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 single-bond geometry to one C(3) atom. In the third H site, H(3) is bonded in a single-bond geometry to one C(4) atom. In the fourth H site, H(4) is bonded in a single-bond geometry to one O(3) atom. The H(4)-O(3) bond length is 0.98 Å. There are three inequivalent O sites. In the first O site, O(1) is bonded in a bent 120 degrees geometry to one Zn(1) and one C(6) atom. In the second O site, O(2) is bonded in a bent 120 degrees geometry to one Zn(1) and one C(6) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to two equivalent Zn(1) and one H(4) atom. Linkers: 2 [O]C(=O)c1ccc2cc(C([O])=O)ccc2c1. Metal clusters: 4 [Zn]. The MOF has largest included sphere 1.68 A, density 2.17 g/cm3, surface area 3274.65 m2/g, accessible volume 0.08 cm3/g