GdC6N3H4O8 crystallizes in the hexagonal P6_3 space group. Gd(1) is bonded in a 9-coordinate geometry to one N(1), one N(2), one O(1), one O(2), one O(3), one O(4), one O(5), one O(6), and one O(8) atom. The Gd(1)-N(1) bond length is 2.60 Å. The Gd(1)-N(2) bond length is 2.61 Å. The Gd(1)-O(1) bond length is 2.38 Å. The Gd(1)-O(2) bond length is 2.35 Å. The Gd(1)-O(3) bond length is 2.39 Å. The Gd(1)-O(4) bond length is 2.36 Å. The Gd(1)-O(5) bond length is 2.50 Å. The Gd(1)-O(6) bond length is 2.42 Å. The Gd(1)-O(8) bond length is 2.48 Å. There are six inequivalent C sites. In the first C site, C(1) is bonded in a trigonal planar geometry to one N(1), one N(2), and one H(1) atom. The C(1)-N(1) bond length is 1.34 Å. The C(1)-N(2) bond length is 1.34 Å. The C(1)-H(1) bond length is 1.09 Å. In the second C site, C(2) is bonded in a distorted single-bond geometry to one C(3) and one N(2) atom. The C(2)-C(3) bond length is 1.39 Å. The C(2)-N(2) bond length is 1.35 Å. In the third C site, C(3) is bonded in a distorted trigonal planar geometry to one C(2), one C(4), and one H(2) atom. The C(3)-C(4) bond length is 1.39 Å. The C(3)-H(2) bond length is 1.08 Å. In the fourth C site, C(4) is bonded in a distorted single-bond geometry to one C(3) and one N(1) atom. The C(4)-N(1) bond length is 1.35 Å. In the fifth C site, C(5) is bonded in a distorted bent 120 degrees geometry to one O(1) and one O(2) atom. The C(5)-O(1) bond length is 1.26 Å. The C(5)-O(2) bond length is 1.26 Å. In the sixth C site, C(6) is bonded in a distorted bent 120 degrees geometry to one O(3) and one O(4) atom. The C(6)-O(3) bond length is 1.26 Å. The C(6)-O(4) bond length is 1.26 Å. There are three inequivalent N sites. In the first N site, N(1) is bonded in a distorted bent 120 degrees geometry to one Gd(1), one C(1), and one C(4) atom. In the second N site, N(2) is bonded in a distorted bent 120 degrees geometry to one Gd(1), one C(1), and one C(2) atom. In the third N site, N(3) is bonded in a trigonal planar geometry to one O(5), one O(6), and one O(7) atom. The N(3)-O(5) bond length is 1.28 Å. The N(3)-O(6) bond length is 1.30 Å. The N(3)-O(7) bond length is 1.23 Å. There are four inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one C(1) 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 O(8) atom. The H(3)-O(8) bond length is 0.98 Å. In the fourth H site, H(4) is bonded in a single-bond geometry to one O(8) atom. The H(4)-O(8) bond length is 0.98 Å. There are eight 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(5) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Gd(1) and one C(5) atom. In the third O site, O(3) is bonded in a distorted bent 120 degrees geometry to one Gd(1) and one C(6) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one Gd(1) and one C(6) atom. In the fifth O site, O(5) is bonded in a distorted L-shaped geometry to one Gd(1) and one N(3) atom. In the sixth O site, O(6) is bonded in a water-like geometry to one Gd(1) and one N(3) atom. In the seventh O site, O(7) is bonded in a single-bond geometry to one N(3) atom. In the eighth O site, O(8) is bonded in a distorted water-like geometry to one Gd(1), one H(3), and one H(4) atom. Linkers: 6 [O]C(=O)c1cc(C([O])=O)ncn1. Metal clusters: 6 [Gd]. The MOF has largest included sphere 3.45 A, density 2.39 g/cm3, surface area 2503.23 m2/g, accessible volume 0.11 cm3/g