MnH8(C5O3)2 crystallizes in the triclinic P-1 space group. Mn(1) is bonded in a 4-coordinate geometry to two equivalent O(1,2) and two equivalent O(3,4) atoms. Both Mn(1)-O(1,2) bond lengths are 2.12 Å. Both Mn(1)-O(3,4) bond lengths are 2.04 Å. There are seven inequivalent C sites. In the first C site, C(1) is bonded in a trigonal planar geometry to one C(3,4); one C(5); and one C(7,8) atom. The C(1)-C(3,4) bond length is 1.42 Å. The C(1)-C(5) bond length is 1.40 Å. The C(1)-C(7,8) bond length is 1.49 Å. In the second C site, C(2) is bonded in a trigonal planar geometry to one C(3,4); one C(6); and one C(7,8) atom. The C(2)-C(3,4) bond length is 1.42 Å. The C(2)-C(6) bond length is 1.40 Å. The C(2)-C(7,8) bond length is 1.49 Å. In the third C site, C(3,4) is bonded in a distorted single-bond geometry to one C(1), one C(5), and one O(5) atom. The C(3,4)-C(5) bond length is 1.39 Å. The C(3,4)-O(5) bond length is 1.37 Å. In the fourth C site, C(5) is bonded in a distorted trigonal planar geometry to one C(1); one C(3,4); and one H(1,2) atom. The C(5)-H(1,2) bond length is 1.09 Å. In the fifth C site, C(6) is bonded in a distorted trigonal planar geometry to one C(2); one C(3,4); and one H(1,2) atom. The C(6)-C(3,4) bond length is 1.39 Å. The C(6)-H(1,2) bond length is 1.09 Å. In the sixth C site, C(7,8) is bonded in a distorted bent 120 degrees geometry to one C(1); one O(1,2); and one O(3,4) atom. The C(7,8)-O(1,2) bond length is 1.28 Å. The C(7,8)-O(3,4) bond length is 1.28 Å. In the seventh C site, C(9,10) is bonded in a tetrahedral geometry to one H(3), one H(5), one H(7), and one O(5) atom. The C(9,10)-H(3) bond length is 1.10 Å. The C(9,10)-H(5) bond length is 1.09 Å. The C(9,10)-H(7) bond length is 1.10 Å. The C(9,10)-O(5) bond length is 1.44 Å. There are seven inequivalent H sites. In the first H site, H(1,2) is bonded in a single-bond geometry to one C(5) atom. In the second H site, H(3) is bonded in a single-bond geometry to one C(9,10) atom. In the third H site, H(4) is bonded in a single-bond geometry to one C(9,10) atom. The H(4)-C(9,10) bond length is 1.10 Å. In the fourth H site, H(5) is bonded in a single-bond geometry to one C(9,10) atom. In the fifth H site, H(6) is bonded in a single-bond geometry to one C(9,10) atom. The H(6)-C(9,10) bond length is 1.09 Å. In the sixth H site, H(7) is bonded in a single-bond geometry to one C(9,10) atom. In the seventh H site, H(8) is bonded in a single-bond geometry to one C(9,10) atom. The H(8)-C(9,10) bond length is 1.10 Å. There are four inequivalent O sites. In the first O site, O(1,2) is bonded in a water-like geometry to one Mn(1) and one C(7,8) atom. In the second O site, O(3,4) is bonded in a bent 120 degrees geometry to one Mn(1) and one C(7,8) atom. In the third O site, O(5) is bonded in a bent 120 degrees geometry to one C(3,4) and one C(9,10) atom. In the fourth O site, O(6) is bonded in a bent 120 degrees geometry to one C(3,4) and one C(9,10) atom. The O(6)-C(3,4) bond length is 1.37 Å. The O(6)-C(9,10) bond length is 1.44 Å. Linkers: 2 COc1cc(C([O])=O)c(OC)cc1C([O])=O. Metal clusters: 2 [Mn]. RCSR code: pts. The MOF has largest included sphere 2.21 A, density 1.76 g/cm3, surface area 3429.43 m2/g, accessible volume 0.12 cm3/g