MnC4H2O3 crystallizes in the trigonal R-3 space group. Mn(1) is bonded to one H(1), one O(1), two equivalent O(2), and two equivalent O(3) atoms to form edge-sharing MnHO5 octahedra. The Mn(1)-H(1) bond length is 1.58 Å. The Mn(1)-O(1) bond length is 2.08 Å. There is one shorter (2.07 Å) and one longer (2.24 Å) Mn(1)-O(2) bond length. There is one shorter (2.00 Å) and one longer (2.02 Å) Mn(1)-O(3) bond length. There are four inequivalent C sites. In the first C site, C(3) is bonded in a single-bond geometry to one C(2), one C(4), and one O(3) atom. The C(3)-C(2) bond length is 1.42 Å. The C(3)-C(4) bond length is 1.39 Å. The C(3)-O(3) bond length is 1.36 Å. In the second C site, C(4) is bonded in a distorted trigonal planar geometry to one C(2), one C(3), and one H(2) atom. The C(4)-C(2) bond length is 1.40 Å. The C(4)-H(2) bond length is 1.09 Å. In the third 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 1.48 Å. The C(1)-O(1) bond length is 1.27 Å. The C(1)-O(2) bond length is 1.30 Å. In the fourth C site, C(2) is bonded in a trigonal planar geometry to one C(1), one C(3), and one C(4) atom. There are two inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one Mn(1) atom. In the second H site, H(2) is bonded in a single-bond geometry to one C(4) atom. There are three inequivalent O sites. In the first O site, O(2) is bonded in a distorted trigonal planar geometry to two equivalent Mn(1) and one C(1) atom. In the second O site, O(3) is bonded in a distorted trigonal planar geometry to two equivalent Mn(1) and one C(3) atom. In the third O site, O(1) is bonded in a bent 120 degrees geometry to one Mn(1) and one C(1) atom. Linkers: 2 [O][C]c1cc([O])c(C([O])=O)cc1[O] ,3 [O]C(=O)c1cc([O])c(C([O])=O)cc1[O]. Metal clusters: 6 [Mn]. The MOF has largest included sphere 10.90 A, density 1.13 g/cm3, surface area 2474.79 m2/g, accessible volume 0.62 cm3/g