CdC2N3H2Br crystallizes in the monoclinic P2_1/c space group. There are three inequivalent Cd sites. In the first Cd site, Cd(1) is bonded to one N(1), one N(3), one N(4), one N(6), and one Br(1) atom to form distorted corner-sharing CdBrN4 trigonal bipyramids. The corner-sharing octahedral tilt angles are 88°. The Cd(1)-N(1) bond length is 2.27 Å. The Cd(1)-N(3) bond length is 2.31 Å. The Cd(1)-N(4) bond length is 2.31 Å. The Cd(1)-N(6) bond length is 2.34 Å. The Cd(1)-Br(1) bond length is 2.70 Å. In the second Cd site, Cd(2) is bonded to one N(2), one N(5), one N(7), one Br(1), one Br(2), and one Br(3) atom to form distorted CdBr3N3 octahedra that share corners with two equivalent Cd(3)Br4N2 octahedra,  a cornercorner with one Cd(1)BrN4 trigonal bipyramid, and  an edgeedge with one Cd(3)Br4N2 octahedra. The corner-sharing octahedral tilt angles range from 41-47°. The Cd(2)-N(2) bond length is 2.31 Å. The Cd(2)-N(5) bond length is 2.36 Å. The Cd(2)-N(7) bond length is 2.31 Å. The Cd(2)-Br(1) bond length is 2.76 Å. The Cd(2)-Br(2) bond length is 3.01 Å. The Cd(2)-Br(3) bond length is 2.87 Å. In the third Cd site, Cd(3) is bonded to one N(8), one N(9), two equivalent Br(2), and two equivalent Br(3) atoms to form distorted CdBr4N2 octahedra that share corners with two equivalent Cd(2)Br3N3 octahedra,  an edgeedge with one Cd(2)Br3N3 octahedra, and edges with two equivalent Cd(3)Br4N2 octahedra. The corner-sharing octahedral tilt angles range from 41-47°. The Cd(3)-N(8) bond length is 2.24 Å. The Cd(3)-N(9) bond length is 2.22 Å. There is one shorter (2.83 Å) and one longer (2.98 Å) Cd(3)-Br(2) bond length. There is one shorter (2.90 Å) and one longer (2.98 Å) Cd(3)-Br(3) bond length. There are six inequivalent C sites. In the first C site, C(1) is bonded in a trigonal planar geometry to one N(1), one N(2), and one H(1) atom. The C(1)-N(1) bond length is 1.34 Å. The C(1)-N(2) bond length is 1.35 Å. The C(1)-H(1) bond length is 1.08 Å. In the second C site, C(2) is bonded in a trigonal planar geometry to one N(2), one N(3), and one H(2) atom. The C(2)-N(2) bond length is 1.35 Å. The C(2)-N(3) bond length is 1.33 Å. The C(2)-H(2) bond length is 1.09 Å. In the third C site, C(3) is bonded in a trigonal planar geometry to one N(4), one N(6), and one H(3) atom. The C(3)-N(4) bond length is 1.33 Å. The C(3)-N(6) bond length is 1.35 Å. The C(3)-H(3) bond length is 1.09 Å. In the fourth C site, C(4) is bonded in a trigonal planar geometry to one N(5), one N(6), and one H(4) atom. The C(4)-N(5) bond length is 1.34 Å. The C(4)-N(6) bond length is 1.36 Å. The C(4)-H(4) bond length is 1.09 Å. In the fifth C site, C(5) is bonded in a trigonal planar geometry to one N(7), one N(9), and one H(5) atom. The C(5)-N(7) bond length is 1.33 Å. The C(5)-N(9) bond length is 1.36 Å. The C(5)-H(5) bond length is 1.09 Å. In the sixth C site, C(6) is bonded in a trigonal planar geometry to one N(8), one N(9), and one H(6) atom. The C(6)-N(8) bond length is 1.33 Å. The C(6)-N(9) bond length is 1.35 Å. The C(6)-H(6) bond length is 1.08 Å. There are nine inequivalent N sites. In the first N site, N(1) is bonded in a distorted trigonal planar geometry to one Cd(1), one C(1), and one N(3) atom. The N(1)-N(3) bond length is 1.37 Å. In the second N site, N(2) is bonded in a distorted trigonal planar geometry to one Cd(2), one C(1), and one C(2) atom. In the third N site, N(3) is bonded in a 3-coordinate geometry to one Cd(1), one C(2), and one N(1) atom. In the fourth N site, N(4) is bonded in a 3-coordinate geometry to one Cd(1), one C(3), and one N(5) atom. The N(4)-N(5) bond length is 1.37 Å. In the fifth N site, N(5) is bonded in a 3-coordinate geometry to one Cd(2), one C(4), and one N(4) atom. In the sixth N site, N(6) is bonded in a distorted trigonal planar geometry to one Cd(1), one C(3), and one C(4) atom. In the seventh N site, N(7) is bonded in a 3-coordinate geometry to one Cd(2), one C(5), and one N(8) atom. The N(7)-N(8) bond length is 1.37 Å. In the eighth N site, N(8) is bonded in a distorted trigonal planar geometry to one Cd(3), one C(6), and one N(7) atom. In the ninth N site, N(9) is bonded in a distorted trigonal planar geometry to one Cd(3), one C(5), and one C(6) atom. 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(2) atom. In the third H site, H(3) is bonded in a single-bond geometry to one C(3) atom. In the fourth H site, H(4) is bonded in a single-bond geometry to one C(4) atom. In the fifth H site, H(5) is bonded in a single-bond geometry to one C(5) atom. In the sixth H site, H(6) is bonded in a single-bond geometry to one C(6) atom. There are three inequivalent Br sites. In the first Br site, Br(1) is bonded in an L-shaped geometry to one Cd(1) and one Cd(2) atom. In the second Br site, Br(2) is bonded in a T-shaped geometry to one Cd(2) and two equivalent Cd(3) atoms. In the third Br site, Br(3) is bonded in a distorted T-shaped geometry to one Cd(2) and two equivalent Cd(3) atoms. Linkers: 8 C1=NN=C[N]1 ,4 [N]1=CN=NC=1. Metal clusters: 12 [Cd]. The MOF has largest included sphere 2.20 A, density 3.17 g/cm3, surface area 2310.61 m2/g, accessible volume 0.09 cm3/g