Ni3H12(C9O8)2 crystallizes in the monoclinic Cm space group. There are three inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(10), one O(9), two equivalent O(1), and two equivalent O(2) atoms to form distorted corner-sharing NiO6 octahedra. The corner-sharing octahedral tilt angles are 58°. The Ni(1)-O(10) bond length is 1.84 Å. The Ni(1)-O(9) bond length is 2.08 Å. Both Ni(1)-O(1) bond lengths are 2.01 Å. Both Ni(1)-O(2) bond lengths are 2.06 Å. In the second Ni site, Ni(2) is bonded to one O(10), one O(7), two equivalent O(4), and two equivalent O(5) atoms to form distorted corner-sharing NiO6 octahedra. The corner-sharing octahedral tilt angles range from 58-63°. The Ni(2)-O(10) bond length is 1.83 Å. The Ni(2)-O(7) bond length is 2.08 Å. Both Ni(2)-O(4) bond lengths are 1.98 Å. Both Ni(2)-O(5) bond lengths are 2.03 Å. In the third Ni site, Ni(3) is bonded to one O(10), one O(8), two equivalent O(3), and two equivalent O(6) atoms to form distorted corner-sharing NiO6 octahedra. The corner-sharing octahedral tilt angles range from 58-63°. The Ni(3)-O(10) bond length is 1.82 Å. The Ni(3)-O(8) bond length is 2.09 Å. Both Ni(3)-O(3) bond lengths are 1.97 Å. Both Ni(3)-O(6) bond lengths are 2.03 Å. There are nine inequivalent C sites. In the first C site, C(1) is bonded in a distorted single-bond geometry to one C(2), one C(3), and one H(1) atom. The C(1)-C(2) bond length is 1.40 Å. The C(1)-C(3) bond length is 1.40 Å. The C(1)-H(1) bond length is 1.09 Å. In the second C site, C(2) is bonded in a trigonal planar geometry to one C(1), one C(4), and one C(8) atom. The C(2)-C(4) bond length is 1.40 Å. The C(2)-C(8) bond length is 1.50 Å. In the third C site, C(3) is bonded in a trigonal planar geometry to one C(1), one C(5), and one C(9) atom. The C(3)-C(5) bond length is 1.40 Å. The C(3)-C(9) bond length is 1.50 Å. In the fourth C site, C(4) is bonded in a distorted single-bond geometry to one C(2), one C(6), and one H(2) atom. The C(4)-C(6) bond length is 1.40 Å. The C(4)-H(2) bond length is 1.09 Å. In the fifth C site, C(5) is bonded in a distorted single-bond geometry to one C(3), one C(6), and one H(3) atom. The C(5)-C(6) bond length is 1.40 Å. The C(5)-H(3) bond length is 1.09 Å. In the sixth C site, C(6) is bonded in a trigonal planar geometry to one C(4), one C(5), and one C(7) atom. The C(6)-C(7) bond length is 1.50 Å. In the seventh C site, C(7) is bonded in a bent 120 degrees geometry to one C(6), one O(5), and one O(6) atom. The C(7)-O(5) bond length is 1.27 Å. The C(7)-O(6) bond length is 1.27 Å. In the eighth C site, C(8) is bonded in a distorted bent 120 degrees geometry to one C(2), one O(1), and one O(3) atom. The C(8)-O(1) bond length is 1.27 Å. The C(8)-O(3) bond length is 1.27 Å. In the ninth C site, C(9) is bonded in a distorted trigonal planar geometry to one C(3), one O(2), and one O(4) atom. The C(9)-O(2) bond length is 1.28 Å. The C(9)-O(4) bond length is 1.27 Å. There are six inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one C(1) atom. In the second H site, H(2) is bonded in a single-bond geometry to one C(4) atom. In the third H site, H(3) is bonded in a single-bond geometry to one C(5) atom. In the fourth H site, H(4) is bonded in a single-bond geometry to one O(7) atom. The H(4)-O(7) bond length is 0.98 Å. In the fifth H site, H(5) is bonded in a single-bond geometry to one O(8) atom. The H(5)-O(8) bond length is 0.98 Å. In the sixth H site, H(6) is bonded in a single-bond geometry to one O(9) atom. The H(6)-O(9) bond length is 0.98 Å. There are ten inequivalent O sites. In the first O site, O(1) is bonded in a bent 120 degrees geometry to one Ni(1) and one C(8) atom. In the second O site, O(2) is bonded in a bent 120 degrees geometry to one Ni(1) and one C(9) atom. In the third O site, O(3) is bonded in a bent 120 degrees geometry to one Ni(3) and one C(8) atom. In the fourth O site, O(4) is bonded in a bent 120 degrees geometry to one Ni(2) and one C(9) atom. In the fifth O site, O(5) is bonded in a bent 120 degrees geometry to one Ni(2) and one C(7) atom. In the sixth O site, O(6) is bonded in a bent 120 degrees geometry to one Ni(3) and one C(7) atom. In the seventh O site, O(7) is bonded in a distorted water-like geometry to one Ni(2) and two equivalent H(4) atoms. In the eighth O site, O(8) is bonded in a distorted water-like geometry to one Ni(3) and two equivalent H(5) atoms. In the ninth O site, O(9) is bonded in a distorted trigonal non-coplanar geometry to one Ni(1) and two equivalent H(6) atoms. In the tenth O site, O(10) is bonded in a trigonal planar geometry to one Ni(1), one Ni(2), and one Ni(3) atom. Linkers: 2 [O]C(=O)c1cc(C([O])=O)cc(C([O])=O)c1. Metal clusters: 1 O.O.O.[C]1O[Ni]23O[C]O[Ni]45(O1)O[C]O[Ni](O[C]O2)(O[C]O3)(O[C]O4)O5. RCSR code: sit. The MOF has largest included sphere 6.99 A, density 1.21 g/cm3, surface area 3281.91 m2/g, accessible volume 0.45 cm3/g