CuC12P2H18(NO4)2 crystallizes in the monoclinic C2/c space group. Cu(1) is bonded to two equivalent N(1), two equivalent O(1), and two equivalent O(2) atoms to form CuN2O4 octahedra that share corners with two equivalent P(1)CO3 tetrahedra. Both Cu(1)-N(1) bond lengths are 2.08 Å. Both Cu(1)-O(1) bond lengths are 2.50 Å. Both Cu(1)-O(2) bond lengths are 2.02 Å. There are six inequivalent C sites. In the first C site, C(1) is bonded in a distorted trigonal non-coplanar geometry to one C(2), one H(4), one H(5), and one H(6) atom. The C(1)-C(2) bond length is 1.50 Å. The C(1)-H(4) bond length is 1.10 Å. The C(1)-H(5) bond length is 1.10 Å. The C(1)-H(6) bond length is 1.10 Å. In the second C site, C(2) is bonded in a trigonal planar geometry to one C(1), one C(3), and one C(4) atom. The C(2)-C(3) bond length is 1.41 Å. The C(2)-C(4) bond length is 1.40 Å. In the third C site, C(3) is bonded in a trigonal planar geometry to one C(2), one C(4), and one P(1) atom. The C(3)-C(4) bond length is 1.40 Å. The C(3)-P(1) bond length is 1.80 Å. In the fourth C site, C(4) is bonded in a distorted single-bond geometry to one C(2), one C(3), and one H(7) atom. The C(4)-H(7) bond length is 1.09 Å. In the fifth C site, C(5) is bonded in a distorted trigonal planar geometry to one N(1) and one H(8) atom. The C(5)-N(1) bond length is 1.34 Å. The C(5)-H(8) bond length is 1.09 Å. In the sixth C site, C(6) is bonded in a distorted trigonal planar geometry to one N(1) and one H(9) atom. The C(6)-N(1) bond length is 1.34 Å. The C(6)-H(9) bond length is 1.09 Å. P(1) is bonded to one C(3), one O(2), one O(3), and one O(4) atom to form PCO3 tetrahedra that share  a cornercorner with one Cu(1)N2O4 octahedra. The corner-sharing octahedral tilt angles are 52°. The P(1)-O(2) bond length is 1.55 Å. The P(1)-O(3) bond length is 1.51 Å. The P(1)-O(4) bond length is 1.59 Å. N(1) is bonded in a trigonal planar geometry to one Cu(1), one C(5), and one C(6) atom. There are nine inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one O(1) atom. The H(1)-O(1) bond length is 0.98 Å. In the second H site, H(2) is bonded in a distorted single-bond geometry to one O(1) and one O(3) atom. The H(2)-O(1) bond length is 1.00 Å. The H(2)-O(3) bond length is 1.68 Å. In the third H site, H(3) is bonded in a distorted single-bond geometry to one O(2) and one O(4) atom. The H(3)-O(2) bond length is 1.65 Å. The H(3)-O(4) bond length is 1.01 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(1) atom. In the sixth H site, H(6) is bonded in a single-bond geometry to one C(1) atom. In the seventh H site, H(7) is bonded in a single-bond geometry to one C(4) atom. In the eighth H site, H(8) is bonded in a single-bond geometry to one C(5) atom. In the ninth H site, H(9) is bonded in a single-bond geometry to one C(6) atom. There are four inequivalent O sites. In the first O site, O(1) is bonded in a water-like geometry to one Cu(1), one H(1), and one H(2) atom. In the second O site, O(2) is bonded in a trigonal planar geometry to one Cu(1), one P(1), and one H(3) atom. In the third O site, O(3) is bonded in a distorted water-like geometry to one P(1) and one H(2) atom. In the fourth O site, O(4) is bonded in a bent 120 degrees geometry to one P(1) and one H(3) atom. Linkers: 2 Cc1cc(P([O])(=O)O)c(C)cc1P([O])O ,2 c1cnccn1 ,2 Cc1cc(P([O])(=O)O)c(C)cc1P([O])(=O)O. Metal clusters: 2 [O]P(O)O[Cu]OP([O])O. The MOF has largest included sphere 1.73 A, density 1.95 g/cm3, surface area 3506.14 m2/g, accessible volume 0.06 cm3/g