GdC5H(NO2)2 crystallizes in the tetragonal I4_1/a space group. There are two inequivalent Gd sites. In the first Gd site, Gd(1) is bonded in a distorted pentagonal pyramidal geometry to one N(2), one N(3), one O(2), one O(3), one O(4), and one O(8) atom. The Gd(1)-N(2) bond length is 2.58 Å. The Gd(1)-N(3) bond length is 2.40 Å. The Gd(1)-O(2) bond length is 2.31 Å. The Gd(1)-O(3) bond length is 2.34 Å. The Gd(1)-O(4) bond length is 2.38 Å. The Gd(1)-O(8) bond length is 2.63 Å. In the second Gd site, Gd(2) is bonded in a 8-coordinate geometry to one N(1), one N(4), one O(1), one O(5), one O(6), one O(8), and two equivalent O(7) atoms. The Gd(2)-N(1) bond length is 2.52 Å. The Gd(2)-N(4) bond length is 2.50 Å. The Gd(2)-O(1) bond length is 2.38 Å. The Gd(2)-O(5) bond length is 2.45 Å. The Gd(2)-O(6) bond length is 2.34 Å. The Gd(2)-O(8) bond length is 2.69 Å. There is one shorter (2.49 Å) and one longer (2.53 Å) Gd(2)-O(7) bond length. There are ten 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 1.35 Å. The C(1)-N(2) bond length is 1.33 Å. The C(1)-H(1) bond length is 1.04 Å. In the second C site, C(2) is bonded in a distorted single-bond geometry to one C(3), one C(5), and one N(2) atom. The C(2)-C(3) bond length is 1.40 Å. The C(2)-C(5) bond length is 1.45 Å. The C(2)-N(2) bond length is 1.38 Å. In the third C site, C(3) is bonded in a distorted single-bond geometry to one C(2) and one N(1) atom. The C(3)-N(1) bond length is 1.37 Å. In the fourth C site, C(4) is bonded in a distorted bent 120 degrees geometry to one O(1) and one O(2) atom. The C(4)-O(1) bond length is 1.29 Å. The C(4)-O(2) bond length is 1.26 Å. In the fifth C site, C(5) is bonded in a distorted bent 120 degrees geometry to one C(2), one O(3), and one O(4) atom. The C(5)-O(3) bond length is 1.25 Å. The C(5)-O(4) bond length is 1.27 Å. In the sixth C site, C(6) is bonded in a trigonal planar geometry to one N(3), one N(4), and one H(2) atom. The C(6)-N(3) bond length is 1.34 Å. The C(6)-N(4) bond length is 1.33 Å. The C(6)-H(2) bond length is 0.91 Å. In the seventh C site, C(7) is bonded in a 3-coordinate geometry to one C(10), one C(8), and one N(3) atom. The C(7)-C(10) bond length is 1.47 Å. The C(7)-C(8) bond length is 1.39 Å. The C(7)-N(3) bond length is 1.38 Å. In the eighth C site, C(8) is bonded in a distorted single-bond geometry to one C(7), one C(9), and one N(4) atom. The C(8)-C(9) bond length is 1.46 Å. The C(8)-N(4) bond length is 1.37 Å. In the ninth C site, C(9) is bonded in a distorted bent 120 degrees geometry to one C(8), one O(5), and one O(6) atom. The C(9)-O(5) bond length is 1.26 Å. The C(9)-O(6) bond length is 1.25 Å. In the tenth C site, C(10) is bonded in a bent 120 degrees geometry to one C(7), one O(7), and one O(8) atom. The C(10)-O(7) bond length is 1.28 Å. The C(10)-O(8) bond length is 1.26 Å. There are four inequivalent N sites. In the first N site, N(1) is bonded in a distorted water-like geometry to one Gd(2), one C(1), and one C(3) atom. In the second N site, N(2) is bonded in a distorted water-like geometry to one Gd(1), one C(1), and one C(2) atom. In the third N site, N(3) is bonded in a distorted trigonal planar geometry to one Gd(1), one C(6), and one C(7) atom. In the fourth N site, N(4) is bonded in a distorted trigonal planar geometry to one Gd(2), one C(6), and one C(8) atom. There are two 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(6) atom. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a bent 120 degrees geometry to one Gd(2) and one C(4) atom. In the second O site, O(2) is bonded in a distorted bent 150 degrees geometry to one Gd(1) and one C(4) atom. In the third O site, O(3) is bonded in a distorted bent 150 degrees geometry to one Gd(1) and one C(5) atom. In the fourth O site, O(4) is bonded in a bent 120 degrees geometry to one Gd(1) and one C(5) atom. In the fifth O site, O(5) is bonded in a bent 120 degrees geometry to one Gd(2) and one C(9) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one Gd(2) and one C(9) atom. In the seventh O site, O(7) is bonded in a distorted single-bond geometry to two equivalent Gd(2) and one C(10) atom. In the eighth O site, O(8) is bonded in a distorted single-bond geometry to one Gd(1), one Gd(2), and one C(10) atom. Linkers: 7 [O]C(=O)[C]1N=CN=C1C([O])=O ,9 [O]C(=O)C1=C(C([O])=O)N=C[N]1. Metal clusters: 16 [Gd]. The MOF has largest included sphere 5.06 A, density 2.49 g/cm3, surface area 1963.30 m2/g, accessible volume 0.16 cm3/g