CsC3N2H3SO3 crystallizes in the monoclinic P2_1/c space group. Cs(1) is bonded in a 10-coordinate geometry to two equivalent N(1), one H(2), two equivalent O(1), two equivalent O(3), and three equivalent O(2) atoms. There is one shorter (3.38 Å) and one longer (3.53 Å) Cs(1)-N(1) bond length. The Cs(1)-H(2) bond length is 3.19 Å. There is one shorter (3.21 Å) and one longer (3.22 Å) Cs(1)-O(1) bond length. There is one shorter (3.30 Å) and one longer (3.43 Å) Cs(1)-O(3) bond length. There are a spread of Cs(1)-O(2) bond distances ranging from 3.12-3.18 Å. There are three inequivalent C sites. In the first C site, C(1) is bonded in a distorted bent 120 degrees geometry to one C(2), one N(2), and one H(2) atom. The C(1)-C(2) bond length is 1.39 Å. The C(1)-N(2) bond length is 1.35 Å. The C(1)-H(2) bond length is 1.08 Å. In the second C site, C(2) is bonded in a trigonal planar geometry to one C(1), one C(3), and one S(1) atom. The C(2)-C(3) bond length is 1.41 Å. The C(2)-S(1) bond length is 1.76 Å. In the third C site, C(3) is bonded in a distorted bent 120 degrees geometry to one C(2), one N(1), and one H(3) atom. The C(3)-N(1) bond length is 1.34 Å. The C(3)-H(3) bond length is 1.08 Å. There are two inequivalent N sites. In the first N site, N(1) is bonded in a distorted single-bond geometry to two equivalent Cs(1) and one C(3) atom. In the second N site, N(2) is bonded in a 2-coordinate geometry to one C(1) and one H(1) atom. The N(2)-H(1) bond length is 1.04 Å. There are three inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one N(2) atom. In the second H site, H(2) is bonded in a single-bond geometry to one Cs(1) and one C(1) atom. In the third H site, H(3) is bonded in a single-bond geometry to one C(3) atom. S(1) is bonded in a distorted tetrahedral geometry to one C(2), one O(1), one O(2), and one O(3) atom. The S(1)-O(1) bond length is 1.49 Å. The S(1)-O(2) bond length is 1.47 Å. The S(1)-O(3) bond length is 1.46 Å. There are three inequivalent O sites. In the first O site, O(1) is bonded in a single-bond geometry to two equivalent Cs(1) and one S(1) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to three equivalent Cs(1) and one S(1) atom. In the third O site, O(3) is bonded in a single-bond geometry to two equivalent Cs(1) and one S(1) atom. Linkers: 4 [O]S([O])([O])c1cn[nH]c1. Metal clusters: 4 [Cs]. The MOF has largest included sphere 1.65 A, density 2.63 g/cm3, surface area 2827.68 m2/g, accessible volume 0.08 cm3/g