CuC2PHO3 crystallizes in the triclinic P-1 space group. There are three inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a rectangular see-saw-like geometry to one O(1), one O(2), one O(3), and one O(4) atom. The Cu(1)-O(1) bond length is 1.94 Å. The Cu(1)-O(2) bond length is 1.88 Å. The Cu(1)-O(3) bond length is 1.92 Å. The Cu(1)-O(4) bond length is 1.94 Å. In the second Cu site, Cu(2) is bonded in a T-shaped geometry to one O(5), one O(8), and one O(9) atom. The Cu(2)-O(5) bond length is 2.02 Å. The Cu(2)-O(8) bond length is 1.93 Å. The Cu(2)-O(9) bond length is 1.93 Å. In the third Cu site, Cu(3) is bonded in a T-shaped geometry to one O(5), one O(6), and one O(7) atom. The Cu(3)-O(5) bond length is 2.04 Å. The Cu(3)-O(6) bond length is 1.95 Å. The Cu(3)-O(7) bond length is 1.89 Å. There are six inequivalent C sites. In the first C site, C(1) is bonded in a trigonal planar geometry to one C(2), one C(6), and one P(1) atom. The C(1)-C(2) bond length is 1.40 Å. The C(1)-C(6) bond length is 1.38 Å. The C(1)-P(1) bond length is 1.80 Å. In the second C site, C(2) is bonded in a distorted single-bond geometry to one C(1), one C(3), and one H(1) atom. The C(2)-C(3) bond length is 1.40 Å. The C(2)-H(1) bond length is 0.97 Å. In the third C site, C(3) is bonded in a distorted trigonal planar geometry to one C(2), one C(4), and one P(2) atom. The C(3)-C(4) bond length is 1.39 Å. The C(3)-P(2) bond length is 1.79 Å. In the fourth C site, C(4) is bonded in a distorted single-bond geometry to one C(3), one C(5), and one H(2) atom. The C(4)-C(5) bond length is 1.39 Å. The C(4)-H(2) bond length is 0.89 Å. In the fifth C site, C(5) is bonded in a trigonal planar geometry to one C(4), one C(6), and one P(3) atom. The C(5)-C(6) bond length is 1.39 Å. The C(5)-P(3) bond length is 1.80 Å. In the sixth C site, C(6) is bonded in a single-bond geometry to one C(1), one C(5), and one H(3) atom. The C(6)-H(3) bond length is 0.85 Å. There are three inequivalent P sites. In the first P site, P(1) is bonded in a tetrahedral geometry to one C(1), one O(2), one O(3), and one O(7) atom. The P(1)-O(2) bond length is 1.50 Å. The P(1)-O(3) bond length is 1.53 Å. The P(1)-O(7) bond length is 1.52 Å. In the second P site, P(2) is bonded in a tetrahedral geometry to one C(3), one O(5), one O(6), and one O(9) atom. The P(2)-O(5) bond length is 1.55 Å. The P(2)-O(6) bond length is 1.52 Å. The P(2)-O(9) bond length is 1.52 Å. In the third P site, P(3) is bonded in a tetrahedral geometry to one C(5), one O(1), one O(4), and one O(8) atom. The P(3)-O(1) bond length is 1.53 Å. The P(3)-O(4) bond length is 1.53 Å. The P(3)-O(8) bond length is 1.53 Å. There are three inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one C(2) atom. In the second H site, H(2) is bonded in a single-bond geometry to one C(4) atom. In the third H site, H(3) is bonded in a single-bond geometry to one C(6) atom. There are nine inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 120 degrees geometry to one Cu(1) and one P(3) atom. In the second O site, O(2) is bonded in a distorted linear geometry to one Cu(1) and one P(1) atom. In the third O site, O(3) is bonded in a distorted bent 150 degrees geometry to one Cu(1) and one P(1) atom. In the fourth O site, O(4) is bonded in a distorted bent 120 degrees geometry to one Cu(1) and one P(3) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Cu(2), one Cu(3), and one P(2) atom. In the sixth O site, O(6) is bonded in a distorted single-bond geometry to one Cu(3) and one P(2) atom. In the seventh O site, O(7) is bonded in a distorted bent 150 degrees geometry to one Cu(3) and one P(1) atom. In the eighth O site, O(8) is bonded in a distorted bent 150 degrees geometry to one Cu(2) and one P(3) atom. In the ninth O site, O(9) is bonded in a distorted bent 120 degrees geometry to one Cu(2) and one P(2) atom. Linkers: 2 [O]P([O])(=O)c1cc(P([O])([O])=O)cc(P([O])([O])=O)c1. Metal clusters: 6 [Cu]. The MOF has largest included sphere 4.87 A, density 1.95 g/cm3, surface area 2344.17 m2/g, accessible volume 0.24 cm3/g