CuC3H2O4 crystallizes in the tetragonal P4_3 space group. Cu(1) is bonded in a rectangular see-saw-like geometry to one O(1), one O(2), one O(3), and one O(4) atom. The Cu(1)-O(1) bond length is 1.93 Å. The Cu(1)-O(2) bond length is 2.24 Å. The Cu(1)-O(3) bond length is 1.97 Å. The Cu(1)-O(4) bond length is 1.97 Å. There are three inequivalent C sites. In the first C site, C(1) is bonded in a distorted trigonal planar geometry to one C(2), one O(1), and one O(2) atom. The C(1)-C(2) bond length is 1.53 Å. The C(1)-O(1) bond length is 1.26 Å. The C(1)-O(2) bond length is 1.23 Å. In the second C site, C(2) is bonded in a water-like geometry to one C(1) and two equivalent H(1,2) atoms. Both C(2)-H(1,2) bond lengths are 0.97 Å. In the third C site, C(3) is bonded in a distorted bent 120 degrees geometry to one O(3) and one O(4) atom. The C(3)-O(3) bond length is 1.25 Å. The C(3)-O(4) bond length is 1.25 Å. H(1,2) is bonded in a single-bond geometry to one C(2) atom. There are four inequivalent O sites. In the first O site, O(1) is bonded in a bent 120 degrees geometry to one Cu(1) and one C(1) atom. In the second O site, O(2) is bonded in a distorted bent 150 degrees geometry to one Cu(1) and one C(1) atom. In the third O site, O(3) is bonded in a bent 120 degrees geometry to one Cu(1) and one C(3) atom. In the fourth O site, O(4) is bonded in a bent 120 degrees geometry to one Cu(1) and one C(3) atom. Linkers: 4 [O]C(=O)CC([O])=O. Metal clusters: 4 [Cu]. The MOF has largest included sphere 4.88 A, density 1.30 g/cm3, surface area 3274.68 m2/g, accessible volume 0.44 cm3/g