CsC7N2H3O7 crystallizes in the monoclinic P2_1/c space group. Cs(1) is bonded in a 10-coordinate geometry to one O(1), one O(3), one O(4), one O(6), two equivalent O(2), two equivalent O(5), and two equivalent O(7) atoms. The Cs(1)-O(1) bond length is 3.40 Å. The Cs(1)-O(3) bond length is 3.00 Å. The Cs(1)-O(4) bond length is 3.25 Å. The Cs(1)-O(6) bond length is 3.39 Å. There is one shorter (3.03 Å) and one longer (3.15 Å) Cs(1)-O(2) bond length. There is one shorter (3.23 Å) and one longer (3.32 Å) Cs(1)-O(5) bond length. There is one shorter (3.36 Å) and one longer (3.38 Å) Cs(1)-O(7) bond length. There are seven inequivalent C sites. In the first C site, C(1) is bonded in a distorted bent 120 degrees geometry to one C(2), one O(1), and one O(2) atom. The C(1)-C(2) bond length is 1.49 Å. The C(1)-O(1) bond length is 1.33 Å. The C(1)-O(2) bond length is 1.24 Å. In the second C site, C(2) is bonded in a trigonal planar geometry to one C(1), one C(3), and one C(7) atom. The C(2)-C(3) bond length is 1.46 Å. The C(2)-C(7) 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), one C(4), and one O(3) atom. The C(3)-C(4) bond length is 1.45 Å. The C(3)-O(3) bond length is 1.28 Å. In the fourth C site, C(4) is bonded in a distorted trigonal planar geometry to one C(3), one C(5), and one N(1) atom. The C(4)-C(5) bond length is 1.39 Å. The C(4)-N(1) bond length is 1.45 Å. In the fifth C site, C(5) is bonded in a distorted single-bond geometry to one C(4), one C(6), and one H(1) atom. The C(5)-C(6) bond length is 1.39 Å. The C(5)-H(1) bond length is 1.09 Å. In the sixth C site, C(6) is bonded in a distorted trigonal planar geometry to one C(5), one C(7), and one N(2) atom. The C(6)-C(7) bond length is 1.40 Å. The C(6)-N(2) bond length is 1.44 Å. In the seventh C site, C(7) is bonded in a distorted single-bond geometry to one C(2), one C(6), and one H(2) atom. The C(7)-H(2) bond length is 1.09 Å. There are two inequivalent N sites. In the first N site, N(1) is bonded in a trigonal planar geometry to one C(4), one O(4), and one O(5) atom. The N(1)-O(4) bond length is 1.24 Å. The N(1)-O(5) bond length is 1.25 Å. In the second N site, N(2) is bonded in a trigonal planar geometry to one C(6), one O(6), and one O(7) atom. The N(2)-O(6) bond length is 1.25 Å. The N(2)-O(7) bond length is 1.25 Å. There are three inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one C(5) atom. In the second H site, H(2) is bonded in a single-bond geometry to one C(7) atom. In the third H site, H(3) is bonded in a bent 150 degrees geometry to one O(1) and one O(3) atom. The H(3)-O(1) bond length is 1.05 Å. The H(3)-O(3) bond length is 1.46 Å. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a water-like geometry to one Cs(1), one C(1), and one H(3) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to two equivalent Cs(1) and one C(1) atom. In the third O site, O(3) is bonded in a distorted water-like geometry to one Cs(1), one C(3), and one H(3) atom. In the fourth O site, O(4) is bonded in a single-bond geometry to one Cs(1) and one N(1) atom. In the fifth O site, O(5) is bonded in a distorted single-bond geometry to two equivalent Cs(1) and one N(1) atom. In the sixth O site, O(6) is bonded in a single-bond geometry to one Cs(1) and one N(2) atom. In the seventh O site, O(7) is bonded in a single-bond geometry to two equivalent Cs(1) and one N(2) atom. Linkers: 4 O=C(O)C1=C[C]([N+](=O)[O-])C=C([N+](=O)[O-])C1=O. Metal clusters: 4 [Cs]. The MOF has largest included sphere 1.79 A, density 2.36 g/cm3, surface area 3211.89 m2/g, accessible volume 0.06 cm3/g