Cd2C9NH9O12 crystallizes in the triclinic P-1 space group. There are two inequivalent Cd sites. In the first Cd site, Cd(1) is bonded to one N(1), one O(1), one O(4), one O(8), one O(9), and two equivalent O(5) atoms to form edge-sharing CdNO6 pentagonal bipyramids. The Cd(1)-N(1) bond length is 2.35 Å. The Cd(1)-O(1) bond length is 2.51 Å. The Cd(1)-O(4) bond length is 2.37 Å. The Cd(1)-O(8) bond length is 2.41 Å. The Cd(1)-O(9) bond length is 2.54 Å. There is one shorter (2.28 Å) and one longer (2.38 Å) Cd(1)-O(5) bond length. In the second Cd site, Cd(2) is bonded in a 6-coordinate geometry to one O(10), one O(11), one O(12), one O(7), and two equivalent O(3) atoms. The Cd(2)-O(10) bond length is 2.55 Å. The Cd(2)-O(11) bond length is 2.39 Å. The Cd(2)-O(12) bond length is 2.34 Å. The Cd(2)-O(7) bond length is 2.23 Å. There is one shorter (2.35 Å) and one longer (2.38 Å) Cd(2)-O(3) bond length. There are nine 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 1.51 Å. The C(1)-O(1) bond length is 1.28 Å. The C(1)-O(2) bond length is 1.26 Å. In the second C site, C(2) is bonded in a distorted trigonal planar geometry to one C(1), one C(3), and one N(1) atom. The C(2)-C(3) bond length is 1.40 Å. The C(2)-N(1) bond length is 1.33 Å. In the third C site, C(3) is bonded in a trigonal planar geometry to one C(2), one C(4), and one C(5) atom. The C(3)-C(4) bond length is 1.50 Å. The C(3)-C(5) bond length is 1.40 Å. In the fourth C site, C(4) is bonded in a distorted bent 120 degrees geometry to one C(3), one O(3), and one O(4) atom. The C(4)-O(3) bond length is 1.29 Å. The C(4)-O(4) bond length is 1.26 Å. In the fifth C site, C(5) is bonded in a distorted trigonal planar geometry to one C(3), one C(6), and one H(9) atom. The C(5)-C(6) bond length is 1.40 Å. The C(5)-H(9) bond length is 1.09 Å. In the sixth C site, C(6) is bonded in a trigonal planar geometry to one C(5), one C(7), and one C(8) atom. The C(6)-C(7) bond length is 1.51 Å. The C(6)-C(8) bond length is 1.40 Å. In the seventh C site, C(7) is bonded in a distorted bent 120 degrees geometry to one C(6), one O(5), and one O(6) atom. The C(7)-O(5) bond length is 1.30 Å. The C(7)-O(6) bond length is 1.24 Å. In the eighth C site, C(8) is bonded in a distorted trigonal planar geometry to one C(6), one C(9), and one N(1) atom. The C(8)-C(9) bond length is 1.50 Å. The C(8)-N(1) bond length is 1.34 Å. In the ninth C site, C(9) is bonded in a distorted bent 120 degrees geometry to one C(8), one O(7), and one O(8) atom. The C(9)-O(7) bond length is 1.28 Å. The C(9)-O(8) bond length is 1.26 Å. N(1) is bonded in a trigonal planar geometry to one Cd(1), one C(2), and one C(8) atom. There are nine inequivalent H sites. In the first H site, H(1) is bonded in a distorted single-bond geometry to one O(1) and one O(9) atom. The H(1)-O(1) bond length is 1.63 Å. The H(1)-O(9) bond length is 1.01 Å. In the second H site, H(2) is bonded in a single-bond geometry to one O(9) atom. The H(2)-O(9) bond length is 0.98 Å. In the third H site, H(3) is bonded in a single-bond geometry to one O(10) atom. The H(3)-O(10) bond length is 1.00 Å. In the fourth H site, H(4) is bonded in a single-bond geometry to one O(10) atom. The H(4)-O(10) bond length is 0.97 Å. In the fifth H site, H(5) is bonded in a single-bond geometry to one O(11) atom. The H(5)-O(11) bond length is 0.98 Å. In the sixth H site, H(6) is bonded in a distorted linear geometry to one O(11) and one O(4) atom. The H(6)-O(11) bond length is 1.01 Å. The H(6)-O(4) bond length is 1.59 Å. In the seventh H site, H(7) is bonded in a distorted single-bond geometry to one O(12) and one O(2) atom. The H(7)-O(12) bond length is 0.99 Å. The H(7)-O(2) bond length is 1.67 Å. In the eighth H site, H(8) is bonded in a single-bond geometry to one O(12) atom. The H(8)-O(12) bond length is 1.00 Å. In the ninth H site, H(9) is bonded in a single-bond geometry to one C(5) atom. There are twelve inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal non-coplanar geometry to one Cd(1), one C(1), and one H(1) atom. In the second O site, O(2) is bonded in a distorted linear geometry to one C(1) and one H(7) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to two equivalent Cd(2) and one C(4) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Cd(1), one C(4), and one H(6) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to two equivalent Cd(1) and one C(7) atom. In the sixth O site, O(6) is bonded in a single-bond geometry to one C(7) atom. In the seventh O site, O(7) is bonded in a water-like geometry to one Cd(2) and one C(9) atom. In the eighth O site, O(8) is bonded in a distorted single-bond geometry to one Cd(1) and one C(9) atom. In the ninth O site, O(9) is bonded in a water-like geometry to one Cd(1), one H(1), and one H(2) atom. In the tenth O site, O(10) is bonded in a water-like geometry to one Cd(2), one H(3), and one H(4) atom. In the eleventh O site, O(11) is bonded in a water-like geometry to one Cd(2), one H(5), and one H(6) atom. In the twelfth O site, O(12) is bonded in a distorted water-like geometry to one Cd(2), one H(7), and one H(8) atom. Linkers: 2 [O]C(=O)c1cc(C([O])=O)c(C([O])=O)nc1C([O])=O. Metal clusters: 4 [Cd]. The MOF has largest included sphere 2.13 A, density 2.64 g/cm3, surface area 2525.75 m2/g, accessible volume 0.09 cm3/g