CuC3H2(N2O)2 crystallizes in the trigonal R-3 space group. Cu(1) is bonded in a rectangular see-saw-like geometry to one N(1), one N(3), one N(4), and one O(1) atom. The Cu(1)-N(1) bond length is 2.02 Å. The Cu(1)-N(3) bond length is 1.98 Å. The Cu(1)-N(4) bond length is 2.00 Å. The Cu(1)-O(1) bond length is 2.00 Å. There are three 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 N(4) atom. The C(1)-N(1) bond length is 1.35 Å. The C(1)-N(4) bond length is 1.31 Å. In the second C site, C(2) is bonded in a distorted bent 120 degrees geometry to one O(1) and one O(2) atom. The C(2)-O(1) bond length is 1.28 Å. The C(2)-O(2) bond length is 1.23 Å. In the third C site, C(3) is bonded in a trigonal planar geometry to one N(1), one N(2), and one N(3) atom. The C(3)-N(1) bond length is 1.35 Å. The C(3)-N(2) bond length is 1.36 Å. The C(3)-N(3) bond length is 1.33 Å. There are four inequivalent N sites. In the first N site, N(1) is bonded in a distorted trigonal planar geometry to one Cu(1), one C(1), and one C(3) atom. In the second N site, N(2) is bonded in a trigonal non-coplanar geometry to one C(3), one H(1), and one H(2) atom. The N(2)-H(1) bond length is 0.86 Å. The N(2)-H(2) bond length is 0.85 Å. In the third N site, N(3) is bonded in a distorted trigonal planar geometry to one Cu(1), one C(3), and one N(4) atom. The N(3)-N(4) bond length is 1.37 Å. In the fourth N site, N(4) is bonded in a 3-coordinate geometry to one Cu(1), one C(1), and one N(3) atom. There are two inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one N(2) atom. In the second H site, H(2) is bonded in a single-bond geometry to one N(2) atom. There are two 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(2) atom. In the second O site, O(2) is bonded in a single-bond geometry to one C(2) atom. Linkers: 1 NC1=NC(C([O])=O)=N[N]1 ,2 NC1=NN=C(C([O])=O)[N]1 ,3 NC1=[N]=C(N=N1)C(=O)[O]. Metal clusters: 6 [Cu]. The MOF has largest included sphere 6.96 A, density 1.58 g/cm3, surface area 3341.52 m2/g, accessible volume 0.32 cm3/g