FeCPH3O7 crystallizes in the monoclinic P2_1/c space group. Fe(1) is bonded to one O(2), one O(3), one O(4), one O(5), one O(6), and one O(7) atom to form FeO6 octahedra that share corners with three equivalent P(1)O4 tetrahedra. The Fe(1)-O(2) bond length is 1.92 Å. The Fe(1)-O(3) bond length is 1.96 Å. The Fe(1)-O(4) bond length is 1.95 Å. The Fe(1)-O(5) bond length is 2.20 Å. The Fe(1)-O(6) bond length is 2.08 Å. The Fe(1)-O(7) bond length is 2.08 Å. C(1) is bonded in a distorted bent 120 degrees geometry to one O(5) and one O(6) atom. The C(1)-O(5) bond length is 1.27 Å. The C(1)-O(6) bond length is 1.26 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 corners with three equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 29-44°. The P(1)-O(1) bond length is 1.58 Å. The P(1)-O(2) bond length is 1.53 Å. The P(1)-O(3) bond length is 1.56 Å. The P(1)-O(4) bond length is 1.53 Å. There are three inequivalent H sites. In the first H site, H(1) is bonded in a distorted single-bond geometry to one O(1) and one O(5) atom. The H(1)-O(1) bond length is 1.00 Å. The H(1)-O(5) bond length is 1.70 Å. In the second H site, H(2) is bonded in a single-bond geometry to one O(7) atom. The H(2)-O(7) bond length is 0.97 Å. In the third H site, H(3) is bonded in a single-bond geometry to one O(7) atom. The H(3)-O(7) bond length is 1.00 Å. There are seven inequivalent O sites. In the first O site, O(3) is bonded in a 2-coordinate geometry to one Fe(1) and one P(1) atom. In the second O site, O(4) is bonded in a bent 150 degrees geometry to one Fe(1) and one P(1) atom. In the third O site, O(5) is bonded in a 3-coordinate geometry to one Fe(1), one C(1), and one H(1) atom. In the fourth O site, O(6) is bonded in a bent 120 degrees geometry to one Fe(1) and one C(1) atom. In the fifth O site, O(7) is bonded in a distorted water-like geometry to one Fe(1), one H(2), and one H(3) atom. In the sixth O site, O(1) is bonded in a bent 120 degrees geometry to one P(1) and one H(1) atom. In the seventh O site, O(2) is bonded in a bent 150 degrees geometry to one Fe(1) and one P(1) atom. Linkers: 2 [O]C(=O)C([O])=O. Metal clusters: 4 [Fe]. The MOF has largest included sphere 2.17 A, density 2.42 g/cm3, surface area 2611.30 m2/g, accessible volume 0.07 cm3/g