TbAgC2H2SO9 crystallizes in the monoclinic C2/m space group. Tb(1) is bonded in a 8-coordinate geometry to one O(1), one O(2), one O(4), one O(7), two equivalent O(3), and two equivalent O(5) atoms. The Tb(1)-O(1) bond length is 2.42 Å. The Tb(1)-O(2) bond length is 2.42 Å. The Tb(1)-O(4) bond length is 2.29 Å. The Tb(1)-O(7) bond length is 2.33 Å. Both Tb(1)-O(3) bond lengths are 2.47 Å. Both Tb(1)-O(5) bond lengths are 2.33 Å. Ag(1) is bonded in a 4-coordinate geometry to one O(1), one O(2), and two equivalent O(3) atoms. The Ag(1)-O(1) bond length is 2.59 Å. The Ag(1)-O(2) bond length is 2.56 Å. Both Ag(1)-O(3) bond lengths are 2.25 Å. There are two 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 two equivalent O(3) atoms. Both C(2)-O(3) bond lengths are 1.27 Å. There are two inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one O(7) atom. The H(1)-O(7) bond length is 0.98 Å. In the second H site, H(2) is bonded in a single-bond geometry to one O(6) and one O(7) atom. The H(2)-O(6) bond length is 1.70 Å. The H(2)-O(7) bond length is 0.99 Å. S(1) is bonded in a tetrahedral geometry to one O(4), one O(6), and two equivalent O(5) atoms. The S(1)-O(4) bond length is 1.49 Å. The S(1)-O(6) bond length is 1.46 Å. Both S(1)-O(5) bond lengths are 1.50 Å. There are seven inequivalent O sites. In the first O site, O(3) is bonded in a distorted trigonal planar geometry to one Tb(1), one Ag(1), and one C(2) atom. In the second O site, O(4) is bonded in a bent 150 degrees geometry to one Tb(1) and one S(1) atom. In the third O site, O(5) is bonded in a bent 150 degrees geometry to one Tb(1) and one S(1) atom. In the fourth O site, O(6) is bonded in a distorted bent 150 degrees geometry to one H(2) and one S(1) atom. In the fifth O site, O(7) is bonded in a distorted water-like geometry to one Tb(1), one H(1), and one H(2) atom. In the sixth O site, O(1) is bonded in a distorted single-bond geometry to one Tb(1), one Ag(1), and one C(1) atom. In the seventh O site, O(2) is bonded in a distorted single-bond geometry to one Tb(1), one Ag(1), and one C(1) atom. Linkers: 1 [O]C(=O)C([O])=O. Metal clusters: 2 [Tb] ,2 [Ag]. The MOF has largest included sphere 1.71 A, density 4.03 g/cm3, surface area 1395.13 m2/g, accessible volume 0.04 cm3/g