Gd2H18(C3O8)3 crystallizes in the trigonal R32 space group. Gd(1) is bonded in a 9-coordinate geometry to three equivalent O(1), three equivalent O(2), and three equivalent O(3) atoms. All Gd(1)-O(1) bond lengths are 2.47 Å. All Gd(1)-O(2) bond lengths are 2.36 Å. All Gd(1)-O(3) bond lengths are 2.45 Å. There are two inequivalent C sites. In the first C site, C(1) is bonded in a distorted bent 120 degrees geometry to two equivalent O(1) atoms. Both C(1)-O(1) bond lengths are 1.40 Å. In the second C site, C(2) is bonded in a distorted bent 120 degrees geometry to one O(3) and one O(4) atom. The C(2)-O(3) bond length is 1.27 Å. The C(2)-O(4) bond length is 1.27 Å. There are three inequivalent H sites. In the first H site, H(1) is bonded in a distorted linear geometry to one O(1) and one O(4) atom. The H(1)-O(1) bond length is 1.02 Å. The H(1)-O(4) bond length is 1.55 Å. In the second H site, H(2) is bonded in a single-bond geometry to one O(2) and one O(4) atom. The H(2)-O(2) bond length is 1.00 Å. The H(2)-O(4) bond length is 1.66 Å. In the third H site, H(3) is bonded in a single-bond geometry to one O(2) atom. The H(3)-O(2) bond length is 0.98 Å. There are four inequivalent O sites. In the first O site, O(3) is bonded in a distorted single-bond geometry to one Gd(1) and one C(2) atom. In the second O site, O(4) is bonded in a distorted trigonal planar geometry to one C(2), one H(1), and one H(2) atom. In the third O site, O(1) is bonded in a distorted bent 120 degrees geometry to one Gd(1), one C(1), and one H(1) atom. In the fourth O site, O(2) is bonded in a distorted water-like geometry to one Gd(1), one H(2), and one H(3) atom. Linkers: 3 [O]C(=O)C(O)(O)C([O])=O. Metal clusters: 2 [Gd]. RCSR code: hcb. The MOF has largest included sphere 4.00 A, density 2.50 g/cm3, surface area 2257.73 m2/g, accessible volume 0.10 cm3/g