CuH2(C3N4)2 crystallizes in the cubic Pm-3m space group. Cu(1) is bonded in a square co-planar geometry to four equivalent N(2) atoms. All Cu(1)-N(2) bond lengths are 2.02 Å. There are three inequivalent C sites. In the first C site, C(1) is bonded in a single-bond geometry to two equivalent C(2) and one H(1) atom. Both C(1)-C(2) bond lengths are 1.40 Å. The C(1)-H(1) bond length is 0.93 Å. In the second C site, C(2) is bonded in a trigonal planar geometry to one C(3) and two equivalent C(1) atoms. The C(2)-C(3) bond length is 1.48 Å. In the third C site, C(3) is bonded in a distorted bent 120 degrees geometry to one C(2) and two equivalent N(1) atoms. Both C(3)-N(1) bond lengths are 1.35 Å. There are two inequivalent N sites. In the first N site, N(1) is bonded in a water-like geometry to one C(3) and one N(2) atom. The N(1)-N(2) bond length is 1.35 Å. In the second N site, N(2) is bonded in a distorted trigonal planar geometry to one Cu(1), one N(1), and one N(2) atom. The N(2)-N(2) bond length is 1.34 Å. H(1) is bonded in a single-bond geometry to one C(1) atom. Linkers: 5 c1c(C2=NN=N[N]2)cc(C2=N[N]N=N2)cc1C1=NN=N[N]1 ,1 c1c(C2=NN=N[N]2)cc(C2=N[N]N=N2)cc1C1=N[N]N=N1 ,2 c1c(C2=NN=N[N]2)cc(C2=NN=N[N]2)cc1C1=NN=N[N]1. Metal clusters: 3 N1=N[Cu]23=NN=[Cu]14N=N[Cu]1(=NN=[Cu](N=N2)(N=N1)N=N3)N=N4. The MOF has largest included sphere 15.53 A, density 0.77 g/cm3, surface area 3617.52 m2/g, accessible volume 0.96 cm3/g