NaGdH4(C2O5)2CH2 crystallizes in the monoclinic P2_1/c space group. The structure consists of four 02329_fluka molecules inside a NaGdH4(C2O5)2 framework. In the NaGdH4(C2O5)2 framework, Na(1) is bonded in a 7-coordinate geometry to one O(1), one O(10), one O(2), one O(3), one O(4), one O(6), and one O(9) atom. The Na(1)-O(1) bond length is 2.44 Å. The Na(1)-O(10) bond length is 2.43 Å. The Na(1)-O(2) bond length is 2.44 Å. The Na(1)-O(3) bond length is 2.36 Å. The Na(1)-O(4) bond length is 2.58 Å. The Na(1)-O(6) bond length is 2.61 Å. The Na(1)-O(9) bond length is 2.35 Å. Gd(1) is bonded in a 9-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(6), one O(7), one O(8), and two equivalent O(5) atoms. The Gd(1)-O(1) bond length is 2.46 Å. The Gd(1)-O(2) bond length is 2.42 Å. The Gd(1)-O(3) bond length is 2.44 Å. The Gd(1)-O(4) bond length is 2.46 Å. The Gd(1)-O(6) bond length is 2.42 Å. The Gd(1)-O(7) bond length is 2.43 Å. The Gd(1)-O(8) bond length is 2.43 Å. There is one shorter (2.40 Å) and one longer (2.56 Å) Gd(1)-O(5) bond length. There are four inequivalent C sites. In the first C site, C(1) is bonded in a distorted bent 120 degrees geometry to one O(1) and one O(2) atom. The C(1)-O(1) bond length is 1.27 Å. The C(1)-O(2) bond length is 1.26 Å. In the second C site, C(2) is bonded in a distorted bent 120 degrees geometry to one O(3) and one O(4) atom. The C(2)-O(3) bond length is 1.26 Å. The C(2)-O(4) bond length is 1.27 Å. In the third C site, C(3) is bonded in a distorted bent 120 degrees geometry to one O(5) and one O(6) atom. The C(3)-O(5) bond length is 1.27 Å. The C(3)-O(6) bond length is 1.25 Å. In the fourth C site, C(4) is bonded in a distorted bent 120 degrees geometry to one O(7) and one O(8) atom. The C(4)-O(7) bond length is 1.28 Å. The C(4)-O(8) bond length is 1.28 Å. There are four inequivalent H sites. In the first H site, H(3) is bonded in a single-bond geometry to one O(9) atom. The H(3)-O(9) bond length is 0.98 Å. In the second H site, H(4) is bonded in a single-bond geometry to one O(9) atom. The H(4)-O(9) bond length is 0.98 Å. In the third H site, H(5) is bonded in a single-bond geometry to one O(10) atom. The H(5)-O(10) bond length is 0.98 Å. In the fourth H site, H(6) is bonded in a single-bond geometry to one O(10) atom. The H(6)-O(10) bond length is 0.98 Å. There are ten inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to one Na(1), one Gd(1), and one C(1) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to one Na(1), one Gd(1), and one C(1) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one Na(1), one Gd(1), and one C(2) atom. In the fourth O site, O(4) is bonded in a distorted single-bond geometry to one Na(1), one Gd(1), and one C(2) atom. In the fifth O site, O(5) is bonded in a distorted single-bond geometry to two equivalent Gd(1) and one C(3) atom. In the sixth O site, O(6) is bonded in a distorted single-bond geometry to one Na(1), one Gd(1), and one C(3) atom. In the seventh O site, O(7) is bonded in a distorted single-bond geometry to one Gd(1) and one C(4) atom. In the eighth O site, O(8) is bonded in a distorted single-bond geometry to one Gd(1) and one C(4) atom. In the ninth O site, O(9) is bonded in a distorted water-like geometry to one Na(1), one H(3), and one H(4) atom. In the tenth O site, O(10) is bonded in a distorted water-like geometry to one Na(1), one H(5), and one H(6) atom. Linkers: 5 [O]C(=O)C([O])=O ,2 [O]C(=O)CCC([O])=O. Metal clusters: 4 [Na] ,4 [Gd]. The MOF has largest included sphere 1.54 A, density 2.92 g/cm3, surface area 1522.99 m2/g, accessible volume 0.02 cm3/g