CdC4P2H10(N3O4)2 crystallizes in the monoclinic P2_1/c space group. Cd(1) is bonded to two equivalent N(2), two equivalent N(3), and two equivalent O(4) atoms to form CdN4O2 octahedra that share corners with two equivalent P(1)O4 tetrahedra. Both Cd(1)-N(2) bond lengths are 2.34 Å. Both Cd(1)-N(3) bond lengths are 2.30 Å. Both Cd(1)-O(4) bond lengths are 2.33 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 H(4) atom. The C(1)-N(1) bond length is 1.33 Å. The C(1)-N(3) bond length is 1.34 Å. The C(1)-H(4) bond length is 1.08 Å. In the second C site, C(2) is bonded in a trigonal planar geometry to one N(2), one N(3), and one H(5) atom. The C(2)-N(2) bond length is 1.33 Å. The C(2)-N(3) bond length is 1.36 Å. The C(2)-H(5) bond length is 1.08 Å. P(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form PO4 tetrahedra that share  a cornercorner with one Cd(1)N4O2 octahedra. The corner-sharing octahedral tilt angles are 19°. The P(1)-O(1) bond length is 1.59 Å. The P(1)-O(2) bond length is 1.59 Å. The P(1)-O(3) bond length is 1.55 Å. The P(1)-O(4) bond length is 1.50 Å. There are three inequivalent N sites. In the first N site, N(1) is bonded in a 2-coordinate geometry to one C(1), one N(2), and one H(3) atom. The N(1)-N(2) bond length is 1.35 Å. The N(1)-H(3) bond length is 1.05 Å. In the second N site, N(2) is bonded in a distorted trigonal planar geometry to one Cd(1), one C(2), and one N(1) atom. In the third N site, N(3) is bonded in a distorted trigonal planar geometry to one Cd(1), one C(1), and one C(2) atom. There are five inequivalent H sites. In the first H site, H(1) is bonded in a distorted linear geometry to one O(1) and one O(3) atom. The H(1)-O(1) bond length is 1.02 Å. The H(1)-O(3) bond length is 1.60 Å. In the second H site, H(2) is bonded in a linear geometry to one O(2) and one O(3) atom. The H(2)-O(2) bond length is 1.01 Å. The H(2)-O(3) bond length is 1.62 Å. In the third H site, H(3) is bonded in a distorted single-bond geometry to one N(1) and one O(3) atom. The H(3)-O(3) bond length is 1.73 Å. In the fourth H site, H(4) is bonded in a single-bond geometry to one C(1) atom. In the fifth H site, H(5) is bonded in a single-bond geometry to one C(2) atom. There are four inequivalent O sites. In the first O site, O(4) is bonded in a distorted bent 150 degrees geometry to one Cd(1) and one P(1) atom. In the second O site, O(1) is bonded in a bent 120 degrees geometry to one P(1) and one H(1) atom. In the third O site, O(2) is bonded in a bent 120 degrees geometry to one P(1) and one H(2) atom. In the fourth O site, O(3) is bonded in a 4-coordinate geometry to one P(1), one H(1), one H(2), and one H(3) atom. Linkers: 4 c1nc[nH]n1. Metal clusters: 2 O=P(O)(O)O[Cd]OP(=O)(O)O. The MOF has largest included sphere 2.90 A, density 2.09 g/cm3, surface area 3350.83 m2/g, accessible volume 0.15 cm3/g