CdH3(CO)5 crystallizes in the monoclinic C2/c space group. Cd(1) is bonded to one O(1), one O(2), one O(5), two equivalent O(3), and two equivalent O(4) atoms to form a mixture of distorted edge and corner-sharing CdO7 pentagonal bipyramids. The Cd(1)-O(1) bond length is 2.32 Å. The Cd(1)-O(2) bond length is 2.35 Å. The Cd(1)-O(5) bond length is 2.27 Å. There is one shorter (2.34 Å) and one longer (2.69 Å) Cd(1)-O(3) bond length. There is one shorter (2.31 Å) and one longer (2.63 Å) Cd(1)-O(4) bond length. There are five inequivalent C sites. In the first C site, C(1) is bonded in a distorted bent 120 degrees geometry to one C(2), one O(1), and one O(2) atom. The C(1)-C(2) bond length is 1.51 Å. The C(1)-O(1) bond length is 1.27 Å. The C(1)-O(2) bond length is 1.27 Å. In the second C site, C(2) is bonded in a trigonal planar geometry to one C(1), one C(2), and one C(3) atom. The C(2)-C(2) bond length is 1.40 Å. The C(2)-C(3) bond length is 1.41 Å. In the third C site, C(3) is bonded in a trigonal planar geometry to one C(2), one C(4), and one C(5) atom. The C(3)-C(4) bond length is 1.40 Å. The C(3)-C(5) bond length is 1.50 Å. In the fourth C site, C(4) is bonded in a distorted single-bond geometry to one C(3) and one H(3) atom. The C(4)-H(3) bond length is 1.09 Å. In the fifth C site, C(5) is bonded in a bent 120 degrees geometry to one C(3), one O(3), and one O(4) atom. The C(5)-O(3) bond length is 1.28 Å. The C(5)-O(4) bond length is 1.28 Å. There are three inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one O(5) atom. The H(1)-O(5) bond length is 1.00 Å. In the second H site, H(2) is bonded in a single-bond geometry to one O(1) and one O(5) atom. The H(2)-O(1) bond length is 1.69 Å. The H(2)-O(5) bond length is 1.00 Å. In the third H site, H(3) is bonded in a single-bond geometry to one C(4) atom. There are five inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal non-coplanar geometry to one Cd(1), one C(1), and one H(2) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to one Cd(1) and one C(1) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to two equivalent Cd(1) and one C(5) atom. In the fourth O site, O(4) is bonded in a 1-coordinate geometry to two equivalent Cd(1) and one C(5) atom. In the fifth O site, O(5) is bonded in a distorted water-like geometry to one Cd(1), one H(1), and one H(2) atom. Linkers: 2 [O]C(=O)c1ccc(C([O])=O)c(C([O])=O)c1C([O])=O. Metal clusters: 4 [Cd]. The MOF has largest included sphere 1.72 A, density 2.93 g/cm3, surface area 2146.86 m2/g, accessible volume 0.04 cm3/g