Gd2Cd3H12(C3O2)12 crystallizes in the tetragonal P4_2/ncm space group. Gd(1) is bonded in a 4-coordinate geometry to two equivalent O(2) and two equivalent O(4) atoms. Both Gd(1)-O(2) bond lengths are 2.34 Å. Both Gd(1)-O(4) bond lengths are 2.35 Å. There are two inequivalent Cd sites. In the first Cd site, Cd(1) is bonded in a distorted square co-planar geometry to two equivalent O(1) and two equivalent O(5) atoms. Both Cd(1)-O(1) bond lengths are 2.22 Å. Both Cd(1)-O(5) bond lengths are 2.26 Å. In the second Cd site, Cd(2) is bonded in a 4-coordinate geometry to four equivalent O(3) atoms. All Cd(2)-O(3) bond lengths are 2.22 Å. There are nine inequivalent C sites. In the first C site, C(1) is bonded in a bent 120 degrees geometry to one C(8), one O(1), and one O(2) atom. The C(1)-C(8) bond length is 1.51 Å. The C(1)-O(1) bond length is 1.25 Å. The C(1)-O(2) bond length is 1.22 Å. In the second C site, C(2) is bonded in a distorted single-bond geometry to one C(4), one C(7), and one H(1) atom. The C(2)-C(4) bond length is 1.38 Å. The C(2)-C(7) bond length is 1.39 Å. The C(2)-H(1) bond length is 0.93 Å. In the third C site, C(3) is bonded in a distorted single-bond geometry to one C(4), one C(8), and one H(2) atom. The C(3)-C(4) bond length is 1.38 Å. The C(3)-C(8) bond length is 1.36 Å. The C(3)-H(2) bond length is 0.93 Å. In the fourth C site, C(4) is bonded in a trigonal planar geometry to one C(2), one C(3), and one C(6) atom. The C(4)-C(6) bond length is 1.49 Å. In the fifth C site, C(5) is bonded in a bent 120 degrees geometry to one C(7), one O(4), and one O(5) atom. The C(5)-C(7) bond length is 1.51 Å. The C(5)-O(4) bond length is 1.24 Å. The C(5)-O(5) bond length is 1.27 Å. In the sixth C site, C(6) is bonded in a bent 120 degrees geometry to one C(4), one O(3), and one O(6) atom. The C(6)-O(3) bond length is 1.28 Å. The C(6)-O(6) bond length is 1.23 Å. In the seventh C site, C(7) is bonded in a trigonal planar geometry to one C(2), one C(5), and one C(9) atom. The C(7)-C(9) bond length is 1.38 Å. In the eighth C site, C(8) is bonded in a trigonal planar geometry to one C(1), one C(3), and one C(9) atom. The C(8)-C(9) bond length is 1.38 Å. In the ninth C site, C(9) is bonded in a distorted single-bond geometry to one C(7), one C(8), and one H(3) atom. The C(9)-H(3) bond length is 0.93 Å. There are three inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one C(2) atom. In the second H site, H(2) is bonded in a single-bond geometry to one C(3) atom. In the third H site, H(3) is bonded in a single-bond geometry to one C(9) atom. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to one Cd(1) and one C(1) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Gd(1) and one C(1) atom. In the third O site, O(3) is bonded in a water-like geometry to one Cd(2) and one C(6) atom. In the fourth O site, O(4) is bonded in a distorted linear geometry to one Gd(1) and one C(5) atom. In the fifth O site, O(5) is bonded in a single-bond geometry to one Cd(1) and one C(5) atom. In the sixth O site, O(6) is bonded in a single-bond geometry to one C(6) atom. Linkers: 16 [O]C(=O)c1cc(C([O])=O)cc(C([O])=O)c1. Metal clusters: 8 [C]1O[Cd]234O[C]O[Gd]2(O1)(O[C]O3)O[C]O4 ,4 O=[C]O[Cd](O[C]=O)(O[C]=O)O[C]=O. RCSR code: mmm. The MOF has largest included sphere 11.12 A, density 0.98 g/cm3, surface area 2993.49 m2/g, accessible volume 0.71 cm3/g