Gd4C2H14(SO6)5 crystallizes in the monoclinic C2/c space group. There are two inequivalent Gd sites. In the first Gd site, Gd(1) is bonded in a 9-coordinate geometry to one O(10), one O(14), one O(15), one O(4), one O(6), one O(7), one O(9), and two equivalent O(5) atoms. The Gd(1)-O(10) bond length is 2.51 Å. The Gd(1)-O(14) bond length is 2.35 Å. The Gd(1)-O(15) bond length is 2.31 Å. The Gd(1)-O(4) bond length is 2.63 Å. The Gd(1)-O(6) bond length is 2.42 Å. The Gd(1)-O(7) bond length is 2.30 Å. The Gd(1)-O(9) bond length is 2.56 Å. There is one shorter (2.40 Å) and one longer (2.63 Å) Gd(1)-O(5) bond length. In the second Gd site, Gd(2) is bonded in a 8-coordinate geometry to one O(1), one O(11), one O(12), one O(13), one O(2), one O(3), one O(8), and one O(9) atom. The Gd(2)-O(1) bond length is 2.42 Å. The Gd(2)-O(11) bond length is 2.29 Å. The Gd(2)-O(12) bond length is 2.31 Å. The Gd(2)-O(13) bond length is 2.40 Å. The Gd(2)-O(2) bond length is 2.45 Å. The Gd(2)-O(3) bond length is 2.38 Å. The Gd(2)-O(8) bond length is 2.36 Å. The Gd(2)-O(9) bond length is 2.46 Å. C(1) is bonded in a trigonal planar geometry to one H(7), one O(5), and one O(9) atom. The C(1)-H(7) bond length is 1.10 Å. The C(1)-O(5) bond length is 1.27 Å. The C(1)-O(9) bond length is 1.27 Å. There are seven inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one O(1) atom. The H(1)-O(1) bond length is 0.98 Å. In the second H site, H(2) is bonded in a single-bond geometry to one O(1) atom. The H(2)-O(1) bond length is 0.97 Å. In the third H site, H(3) is bonded in a single-bond geometry to one O(13) and one O(3) atom. The H(3)-O(13) bond length is 1.74 Å. The H(3)-O(3) bond length is 0.99 Å. In the fourth H site, H(4) is bonded in a single-bond geometry to one O(3) atom. The H(4)-O(3) bond length is 0.98 Å. In the fifth H site, H(5) is bonded in a single-bond geometry to one O(4) atom. The H(5)-O(4) bond length is 0.99 Å. In the sixth H site, H(6) is bonded in a single-bond geometry to one O(4) atom. The H(6)-O(4) bond length is 0.99 Å. In the seventh H site, H(7) is bonded in a single-bond geometry to one C(1) atom. There are three inequivalent S sites. In the first S site, S(1) is bonded in a tetrahedral geometry to one O(10), one O(11), one O(7), and one O(8) atom. The S(1)-O(10) bond length is 1.49 Å. The S(1)-O(11) bond length is 1.48 Å. The S(1)-O(7) bond length is 1.49 Å. The S(1)-O(8) bond length is 1.49 Å. In the second S site, S(2) is bonded in a tetrahedral geometry to one O(13), one O(15), one O(2), and one O(6) atom. The S(2)-O(13) bond length is 1.49 Å. The S(2)-O(15) bond length is 1.47 Å. The S(2)-O(2) bond length is 1.49 Å. The S(2)-O(6) bond length is 1.49 Å. In the third S site, S(3) is bonded in a tetrahedral geometry to two equivalent O(12) and two equivalent O(14) atoms. Both S(3)-O(12) bond lengths are 1.48 Å. Both S(3)-O(14) bond lengths are 1.49 Å. There are fifteen inequivalent O sites. In the first O site, O(8) is bonded in a bent 150 degrees geometry to one Gd(2) and one S(1) atom. In the second O site, O(9) is bonded in a distorted single-bond geometry to one Gd(1), one Gd(2), and one C(1) atom. In the third O site, O(10) is bonded in a distorted single-bond geometry to one Gd(1) and one S(1) atom. In the fourth O site, O(11) is bonded in a bent 150 degrees geometry to one Gd(2) and one S(1) atom. In the fifth O site, O(12) is bonded in a bent 150 degrees geometry to one Gd(2) and one S(3) atom. In the sixth O site, O(13) is bonded in a 3-coordinate geometry to one Gd(2), one H(3), and one S(2) atom. In the seventh O site, O(14) is bonded in a distorted bent 150 degrees geometry to one Gd(1) and one S(3) atom. In the eighth O site, O(15) is bonded in a bent 150 degrees geometry to one Gd(1) and one S(2) atom. In the ninth O site, O(1) is bonded in a distorted water-like geometry to one Gd(2), one H(1), and one H(2) atom. In the tenth O site, O(2) is bonded in a distorted single-bond geometry to one Gd(2) and one S(2) atom. In the eleventh O site, O(3) is bonded in a distorted water-like geometry to one Gd(2), one H(3), and one H(4) atom. In the twelfth O site, O(4) is bonded in a distorted water-like geometry to one Gd(1), one H(5), and one H(6) atom. In the thirteenth O site, O(5) is bonded in a distorted single-bond geometry to two equivalent Gd(1) and one C(1) atom. In the fourteenth O site, O(6) is bonded in a distorted bent 120 degrees geometry to one Gd(1) and one S(2) atom. In the fifteenth O site, O(7) is bonded in a distorted bent 150 degrees geometry to one Gd(1) and one S(1) atom. Linkers: 10 [O]S([O])(=O)=O ,4 [O]C=O. Metal clusters: 8 [Gd]. The MOF has largest included sphere 2.50 A, density 3.65 g/cm3, surface area 1445.59 m2/g, accessible volume 0.03 cm3/g