Gd2H12(C4O5)3 crystallizes in the orthorhombic Ama2 space group. There are two inequivalent Gd sites. In the first Gd site, Gd(1) is bonded in a 9-coordinate geometry to one O(8), two equivalent O(1), two equivalent O(3), two equivalent O(5), and two equivalent O(6) atoms. The Gd(1)-O(8) bond length is 2.47 Å. Both Gd(1)-O(1) bond lengths are 2.41 Å. Both Gd(1)-O(3) bond lengths are 2.49 Å. Both Gd(1)-O(5) bond lengths are 2.44 Å. Both Gd(1)-O(6) bond lengths are 2.42 Å. In the second Gd site, Gd(2) is bonded in a distorted pentagonal pyramidal geometry to two equivalent O(2), two equivalent O(4), and two equivalent O(7) atoms. Both Gd(2)-O(2) bond lengths are 2.33 Å. Both Gd(2)-O(4) bond lengths are 2.36 Å. Both Gd(2)-O(7) bond lengths are 2.36 Å. There are six inequivalent C sites. In the first C site, C(1) is bonded in a distorted trigonal planar geometry to one C(2), one O(1), and one O(2) atom. The C(1)-C(2) bond length is 1.48 Å. The C(1)-O(1) bond length is 1.25 Å. The C(1)-O(2) bond length is 1.25 Å. In the second C site, C(2) is bonded in a distorted trigonal non-coplanar geometry to one C(1); two equivalent H(1,2); and one O(3) atom. Both C(2)-H(1,2) bond lengths are 0.97 Å. The C(2)-O(3) bond length is 1.41 Å. In the third C site, C(3) is bonded in a distorted trigonal non-coplanar geometry to one C(4), one H(3), one H(4), and one O(3) atom. The C(3)-C(4) bond length is 1.49 Å. The C(3)-H(3) bond length is 0.97 Å. The C(3)-H(4) bond length is 0.97 Å. The C(3)-O(3) bond length is 1.42 Å. In the fourth C site, C(4) is bonded in a distorted trigonal planar geometry to one C(3), one O(4), and one O(5) atom. The C(4)-O(4) bond length is 1.24 Å. The C(4)-O(5) bond length is 1.28 Å. In the fifth C site, C(5) is bonded in a distorted trigonal planar geometry to one C(6), one O(6), and one O(7) atom. The C(5)-C(6) bond length is 1.51 Å. The C(5)-O(6) bond length is 1.26 Å. The C(5)-O(7) bond length is 1.24 Å. In the sixth C site, C(6) is bonded in a distorted trigonal non-coplanar geometry to one C(5), one H(5), one H(6), and one O(8) atom. The C(6)-H(5) bond length is 0.97 Å. The C(6)-H(6) bond length is 0.97 Å. The C(6)-O(8) bond length is 1.41 Å. There are five inequivalent H sites. In the first H site, H(1,2) is bonded in a single-bond geometry to one C(2) atom. In the second H site, H(3) is bonded in a single-bond geometry to one C(3) atom. In the third H site, H(4) is bonded in a single-bond geometry to one C(3) atom. In the fourth H site, H(5) is bonded in a single-bond geometry to one C(6) atom. In the fifth H site, H(6) is bonded in a single-bond geometry to one C(6) atom. There are eight inequivalent O sites. In the first O site, O(8) is bonded in a distorted bent 120 degrees geometry to one Gd(1) and two equivalent C(6) atoms. In the second O site, O(1) is bonded in a distorted bent 120 degrees geometry to one Gd(1) and one C(1) atom. In the third O site, O(2) is bonded in a bent 150 degrees geometry to one Gd(2) and one C(1) atom. In the fourth O site, O(3) is bonded in a distorted bent 120 degrees geometry to one Gd(1), one C(2), and one C(3) atom. In the fifth O site, O(4) is bonded in a distorted bent 150 degrees geometry to one Gd(2) and one C(4) atom. In the sixth O site, O(5) is bonded in a distorted bent 120 degrees geometry to one Gd(1) and one C(4) atom. In the seventh O site, O(6) is bonded in a distorted bent 120 degrees geometry to one Gd(1) and one C(5) atom. In the eighth O site, O(7) is bonded in a bent 150 degrees geometry to one Gd(2) and one C(5) atom. Linkers: 6 [O]C(=O)COCC([O])=O. Metal clusters: 4 [Gd]. The MOF has largest included sphere 5.75 A, density 1.91 g/cm3, surface area 2627.49 m2/g, accessible volume 0.24 cm3/g