CdC2N9H3O crystallizes in the monoclinic P2_1/c space group. Cd(1) is bonded in a distorted octahedral geometry to one N(1), one N(3), one N(4), one N(6), one N(7), and one O(1) atom. The Cd(1)-N(1) bond length is 2.36 Å. The Cd(1)-N(3) bond length is 2.37 Å. The Cd(1)-N(4) bond length is 2.39 Å. The Cd(1)-N(6) bond length is 2.43 Å. The Cd(1)-N(7) bond length is 2.36 Å. The Cd(1)-O(1) bond length is 2.34 Å. There are two inequivalent C sites. In the first C site, C(1) is bonded in a trigonal planar geometry to one N(1), one N(3), and one N(9) atom. The C(1)-N(1) bond length is 1.35 Å. The C(1)-N(3) bond length is 1.35 Å. The C(1)-N(9) bond length is 1.36 Å. In the second C site, C(2) is bonded in a trigonal planar geometry to one N(7), one N(8), and one N(9) atom. The C(2)-N(7) bond length is 1.35 Å. The C(2)-N(8) bond length is 1.34 Å. The C(2)-N(9) bond length is 1.37 Å. There are nine inequivalent N sites. In the first N site, N(3) is bonded in a 3-coordinate geometry to one Cd(1), one C(1), and one N(5) atom. The N(3)-N(5) bond length is 1.35 Å. In the second N site, N(4) is bonded in a trigonal planar geometry to one Cd(1), one N(1), and one N(5) atom. The N(4)-N(1) bond length is 1.35 Å. The N(4)-N(5) bond length is 1.30 Å. In the third N site, N(5) is bonded in a distorted water-like geometry to one N(3) and one N(4) atom. In the fourth N site, N(6) is bonded in a trigonal planar geometry to one Cd(1), one N(2), and one N(8) atom. The N(6)-N(2) bond length is 1.31 Å. The N(6)-N(8) bond length is 1.35 Å. In the fifth N site, N(7) is bonded in a distorted trigonal planar geometry to one Cd(1), one C(2), and one N(2) atom. The N(7)-N(2) bond length is 1.35 Å. In the sixth N site, N(8) is bonded in a 3-coordinate geometry to one C(2), one N(6), and one H(2) atom. The N(8)-H(2) bond length is 1.74 Å. In the seventh N site, N(1) is bonded in a distorted trigonal planar geometry to one Cd(1), one C(1), and one N(4) atom. In the eighth N site, N(9) is bonded in a trigonal planar geometry to one C(1), one C(2), and one H(1) atom. The N(9)-H(1) bond length is 1.04 Å. In the ninth N site, N(2) is bonded in a 2-coordinate geometry to one N(6) and one N(7) atom. There are three inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one N(9) atom. In the second H site, H(2) is bonded in a single-bond geometry to one N(8) and one O(1) atom. The H(2)-O(1) bond length is 1.00 Å. In the third H site, H(3) is bonded in a single-bond geometry to one O(1) atom. The H(3)-O(1) bond length is 1.00 Å. O(1) is bonded in a distorted water-like geometry to one Cd(1), one H(2), and one H(3) atom. Linkers: 4 [N]1N=NN=C1NC1=NN=N[N]1. Metal clusters: 2 N1=N[Cd]=NN=[Cd]1.O.O. The MOF has largest included sphere 1.87 A, density 2.71 g/cm3, surface area 2601.22 m2/g, accessible volume 0.09 cm3/g