GdC3N9H8O5 crystallizes in the monoclinic Cm space group. Gd(1) is bonded in a pentagonal bipyramidal geometry to two equivalent N(1), one O(1), one O(2), one O(3), and two equivalent O(4) atoms. Both Gd(1)-N(1) bond lengths are 2.49 Å. The Gd(1)-O(1) bond length is 2.38 Å. The Gd(1)-O(2) bond length is 2.30 Å. The Gd(1)-O(3) bond length is 2.44 Å. Both Gd(1)-O(4) bond lengths are 2.31 Å. There are two inequivalent C sites. In the first C site, C(1) is bonded in a trigonal planar geometry to one N(1), one N(4), and one N(5) atom. The C(1)-N(1) bond length is 1.34 Å. The C(1)-N(4) bond length is 1.34 Å. The C(1)-N(5) bond length is 1.36 Å. In the second C site, C(2) is bonded in a trigonal planar geometry to one H(5), one O(1), and one O(2) atom. The C(2)-H(5) bond length is 1.11 Å. The C(2)-O(1) bond length is 1.25 Å. The C(2)-O(2) bond length is 1.28 Å. There are five inequivalent N sites. In the first N site, N(5) is bonded in a distorted trigonal planar geometry to two equivalent C(1) and one H(4) atom. The N(5)-H(4) bond length is 1.03 Å. In the second N site, N(1) is bonded in a distorted trigonal planar geometry to one Gd(1), one C(1), and one N(2) atom. The N(1)-N(2) bond length is 1.36 Å. In the third N site, N(2) is bonded in a 3-coordinate geometry to one N(1), one N(3), and one H(2) atom. The N(2)-N(3) bond length is 1.30 Å. The N(2)-H(2) bond length is 1.80 Å. In the fourth N site, N(3) is bonded in a 3-coordinate geometry to one N(2), one N(4), and one H(1) atom. The N(3)-N(4) bond length is 1.35 Å. The N(3)-H(1) bond length is 1.79 Å. In the fifth N site, N(4) is bonded in a 3-coordinate geometry to one C(1), one N(3), and one H(3) atom. The N(4)-H(3) bond length is 1.64 Å. There are five inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one N(3) and one O(3) atom. The H(1)-O(3) bond length is 1.01 Å. In the second H site, H(2) is bonded in a single-bond geometry to one N(2) and one O(4) atom. The H(2)-O(4) bond length is 0.99 Å. In the third H site, H(3) is bonded in a distorted linear geometry to one N(4) and one O(4) atom. The H(3)-O(4) bond length is 1.02 Å. In the fourth H site, H(4) is bonded in a single-bond geometry to one N(5) atom. In the fifth H site, H(5) is bonded in a single-bond geometry to one C(2) atom. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 120 degrees geometry to one Gd(1) and one C(2) atom. In the second O site, O(2) is bonded in a distorted linear geometry to one Gd(1) and one C(2) atom. In the third O site, O(3) is bonded in a water-like geometry to one Gd(1) and two equivalent H(1) atoms. In the fourth O site, O(4) is bonded in a distorted water-like geometry to one Gd(1), one H(2), and one H(3) atom. Linkers: 1 [N]1N=NN=C1NC1=NN=N[N]1 ,1 [O]C=O. Metal clusters: 1 [Gd]. The MOF has largest included sphere 2.08 A, density 2.57 g/cm3, surface area 2773.29 m2/g, accessible volume 0.07 cm3/g