Mn3C4N20H12(OCl)2 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to two equivalent N(2), two equivalent N(8), and two equivalent Cl(1) atoms to form corner-sharing MnN4Cl2 octahedra. The corner-sharing octahedral tilt angles are 88°. Both Mn(1)-N(2) bond lengths are 2.25 Å. Both Mn(1)-N(8) bond lengths are 2.21 Å. Both Mn(1)-Cl(1) bond lengths are 2.59 Å. In the second Mn site, Mn(2) is bonded to one N(1), one N(4), one N(6), one N(9), one O(1), and one Cl(1) atom to form corner-sharing MnN4ClO octahedra. The corner-sharing octahedral tilt angles are 88°. The Mn(2)-N(1) bond length is 2.23 Å. The Mn(2)-N(4) bond length is 2.22 Å. The Mn(2)-N(6) bond length is 2.23 Å. The Mn(2)-N(9) bond length is 2.21 Å. The Mn(2)-O(1) bond length is 2.30 Å. The Mn(2)-Cl(1) bond length is 2.56 Å. There are two inequivalent C sites. In the first C site, C(1) is bonded in a trigonal planar geometry to one N(1), one N(4), and one N(5) atom. The C(1)-N(1) bond length is 1.34 Å. The C(1)-N(4) bond length is 1.35 Å. The C(1)-N(5) bond length is 1.37 Å. In the second C site, C(2) is bonded in a trigonal planar geometry to one N(10), one N(6), and one N(9) atom. The C(2)-N(10) bond length is 1.34 Å. The C(2)-N(6) bond length is 1.36 Å. The C(2)-N(9) bond length is 1.35 Å. There are ten inequivalent N sites. In the first N site, N(1) is bonded in a distorted trigonal planar geometry to one Mn(2), one C(1), and one N(2) atom. The N(1)-N(2) bond length is 1.35 Å. In the second N site, N(2) is bonded in a distorted trigonal planar geometry to one Mn(1), one N(1), and one N(3) atom. The N(2)-N(3) bond length is 1.31 Å. In the third N site, N(3) is bonded in a water-like geometry to one N(2) and one N(4) atom. The N(3)-N(4) bond length is 1.35 Å. In the fourth N site, N(4) is bonded in a distorted trigonal planar geometry to one Mn(2), one C(1), and one N(3) atom. In the fifth N site, N(5) is bonded in a distorted trigonal non-coplanar geometry to one C(1), one H(3), and one H(4) atom. The N(5)-H(3) bond length is 1.03 Å. The N(5)-H(4) bond length is 1.02 Å. In the sixth N site, N(6) is bonded in a distorted trigonal planar geometry to one Mn(2), one C(2), and one N(7) atom. The N(6)-N(7) bond length is 1.35 Å. In the seventh N site, N(7) is bonded in a water-like geometry to one N(6) and one N(8) atom. The N(7)-N(8) bond length is 1.30 Å. In the eighth N site, N(8) is bonded in a distorted trigonal planar geometry to one Mn(1), one N(7), and one N(9) atom. The N(8)-N(9) bond length is 1.35 Å. In the ninth N site, N(9) is bonded in a distorted trigonal planar geometry to one Mn(2), one C(2), and one N(8) atom. In the tenth N site, N(10) is bonded in a trigonal planar geometry to one C(2), one H(5), and one H(6) atom. The N(10)-H(5) bond length is 1.02 Å. The N(10)-H(6) bond length is 1.01 Å. There are six inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one O(1) atom. The H(1)-O(1) bond length is 0.98 Å. In the second H site, H(2) is bonded in a single-bond geometry to one O(1) atom. The H(2)-O(1) bond length is 0.99 Å. In the third H site, H(3) is bonded in a single-bond geometry to one N(5) atom. In the fourth H site, H(4) is bonded in a single-bond geometry to one N(5) atom. In the fifth H site, H(5) is bonded in a single-bond geometry to one N(10) atom. In the sixth H site, H(6) is bonded in a single-bond geometry to one N(10) atom. O(1) is bonded in a distorted water-like geometry to one Mn(2), one H(1), and one H(2) atom. Cl(1) is bonded in an L-shaped geometry to one Mn(1) and one Mn(2) atom. Linkers: 8 NC1=NN=N[N]1. Metal clusters: 2 Cl[Mn]1[N]N=[Mn]2(N=N1)N=N[Mn](Cl)N=N2.O.O. The MOF has largest included sphere 3.56 A, density 1.82 g/cm3, surface area 3075.89 m2/g, accessible volume 0.16 cm3/g