Fe2C4O9Cl2 crystallizes in the orthorhombic Fdd2 space group. Fe(1) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one Cl(1) atom to form distorted corner-sharing FeClO5 octahedra. The corner-sharing octahedral tilt angles are 44°. The Fe(1)-O(1) bond length is 2.01 Å. The Fe(1)-O(2) bond length is 2.16 Å. The Fe(1)-O(3) bond length is 2.00 Å. The Fe(1)-O(4) bond length is 2.13 Å. The Fe(1)-O(5) bond length is 1.87 Å. The Fe(1)-Cl(1) bond length is 2.29 Å. There are two inequivalent C sites. In the first C site, C(1) is bonded in a distorted bent 120 degrees geometry to one O(1) and one O(4) atom. The C(1)-O(1) bond length is 1.24 Å. The C(1)-O(4) bond length is 1.24 Å. In the second C site, C(2) is bonded in a distorted bent 120 degrees geometry to one O(2) and one O(3) atom. The C(2)-O(2) bond length is 1.22 Å. The C(2)-O(3) bond length is 1.28 Å. There are five inequivalent O sites. In the first O site, O(1) is bonded in a bent 120 degrees geometry to one Fe(1) and one C(1) atom. In the second O site, O(2) is bonded in a bent 120 degrees geometry to one Fe(1) and one C(2) atom. In the third O site, O(3) is bonded in a bent 120 degrees geometry to one Fe(1) and one C(2) atom. In the fourth O site, O(4) is bonded in a bent 120 degrees geometry to one Fe(1) and one C(1) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to two equivalent Fe(1) atoms. Cl(1) is bonded in a single-bond geometry to one Fe(1) atom. Linkers: 16 [O]C(=O)C([O])=O. Metal clusters: 16 [Fe]. The MOF has largest included sphere 3.95 A, density 1.56 g/cm3, surface area 3280.08 m2/g, accessible volume 0.31 cm3/g