BaC4H10(N4O3)2 crystallizes in the triclinic P-1 space group. Ba(1) is bonded in a 9-coordinate geometry to one N(7), one O(2), one O(6), two equivalent O(3), two equivalent O(4), and two equivalent O(5) atoms. The Ba(1)-N(7) bond length is 2.96 Å. The Ba(1)-O(2) bond length is 2.79 Å. The Ba(1)-O(6) bond length is 2.78 Å. There is one shorter (2.72 Å) and one longer (2.85 Å) Ba(1)-O(3) bond length. There is one shorter (2.73 Å) and one longer (2.81 Å) Ba(1)-O(4) bond length. There is one shorter (2.91 Å) and one longer (3.23 Å) Ba(1)-O(5) bond length. There are four inequivalent C sites. In the first C site, C(1) is bonded in a trigonal planar geometry to one N(3), one N(5), and one O(1) atom. The C(1)-N(3) bond length is 1.40 Å. The C(1)-N(5) bond length is 1.34 Å. The C(1)-O(1) bond length is 1.27 Å. In the second C site, C(2) is bonded in a trigonal planar geometry to one N(4), one N(8), and one H(1) atom. The C(2)-N(4) bond length is 1.38 Å. The C(2)-N(8) bond length is 1.31 Å. The C(2)-H(1) bond length is 1.08 Å. In the third C site, C(3) is bonded in a trigonal planar geometry to one N(4), one N(7), and one O(2) atom. The C(3)-N(4) bond length is 1.43 Å. The C(3)-N(7) bond length is 1.35 Å. The C(3)-O(2) bond length is 1.26 Å. In the fourth C site, C(4) is bonded in a trigonal planar geometry to one N(3), one N(6), and one H(2) atom. The C(4)-N(3) bond length is 1.39 Å. The C(4)-N(6) bond length is 1.31 Å. The C(4)-H(2) bond length is 1.08 Å. There are eight inequivalent N sites. In the first N site, N(1) is bonded in a water-like geometry to one N(2) and one N(4) atom. The N(1)-N(2) bond length is 1.26 Å. The N(1)-N(4) bond length is 1.35 Å. In the second N site, N(2) is bonded in a bent 120 degrees geometry to one N(1) and one N(3) atom. The N(2)-N(3) bond length is 1.36 Å. In the third N site, N(3) is bonded in a distorted water-like geometry to one C(1), one C(4), and one N(2) atom. In the fourth N site, N(4) is bonded in a distorted trigonal planar geometry to one C(2), one C(3), and one N(1) atom. In the fifth N site, N(5) is bonded in a distorted single-bond geometry to one C(1) and one N(6) atom. The N(5)-N(6) bond length is 1.39 Å. In the sixth N site, N(6) is bonded in a distorted water-like geometry to one C(4) and one N(5) atom. In the seventh N site, N(7) is bonded in a distorted single-bond geometry to one Ba(1) and one C(3) atom. In the eighth N site, N(8) is bonded in a distorted single-bond geometry to one C(2) atom. There are ten inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one C(2) 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 distorted linear geometry to one O(1) and one O(3) atom. The H(3)-O(1) bond length is 1.65 Å. The H(3)-O(3) bond length is 1.00 Å. In the fourth H site, H(4) is bonded in a single-bond geometry to one O(3) atom. The H(4)-O(3) bond length is 0.99 Å. In the fifth H site, H(5) is bonded in a single-bond geometry to one O(1) and one O(4) atom. The H(5)-O(1) bond length is 1.71 Å. The H(5)-O(4) bond length is 0.99 Å. In the sixth H site, H(6) is bonded in a single-bond geometry to one O(4) atom. The H(6)-O(4) bond length is 1.00 Å. In the seventh H site, H(7) is bonded in a single-bond geometry to one O(5) atom. The H(7)-O(5) bond length is 0.99 Å. In the eighth H site, H(8) is bonded in a single-bond geometry to one O(5) atom. The H(8)-O(5) bond length is 0.99 Å. In the ninth H site, H(9) is bonded in a single-bond geometry to one O(6) atom. The H(9)-O(6) bond length is 0.98 Å. In the tenth H site, H(10) is bonded in a single-bond geometry to one O(6) atom. The H(10)-O(6) bond length is 0.99 Å. There are six inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one C(1), one H(3), and one H(5) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to one Ba(1) and one C(3) atom. In the third O site, O(3) is bonded in a water-like geometry to two equivalent Ba(1), one H(3), and one H(4) atom. In the fourth O site, O(4) is bonded in a water-like geometry to two equivalent Ba(1), one H(5), and one H(6) atom. In the fifth O site, O(5) is bonded in a water-like geometry to two equivalent Ba(1), one H(7), and one H(8) atom. In the sixth O site, O(6) is bonded in a water-like geometry to one Ba(1), one H(10), and one H(9) atom. Linkers: 2 O=C1[N]N=CN1[N][N]N1C=N[N]C1=O ,4 O. Metal clusters: 2 [Ba]. The MOF has largest included sphere 1.68 A, density 2.25 g/cm3, surface area 3486.34 m2/g, accessible volume 0.10 cm3/g