Ba7C24(NO18)2 crystallizes in the monoclinic C2 space group. There are four inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 10-coordinate geometry to one O(1), one O(14), one O(15), one O(16), one O(18), one O(3), one O(4), one O(7), one O(8), and one O(9) atom. The Ba(1)-O(1) bond length is 2.75 Å. The Ba(1)-O(14) bond length is 2.93 Å. The Ba(1)-O(15) bond length is 2.96 Å. The Ba(1)-O(16) bond length is 2.86 Å. The Ba(1)-O(18) bond length is 3.04 Å. The Ba(1)-O(3) bond length is 2.71 Å. The Ba(1)-O(4) bond length is 2.82 Å. The Ba(1)-O(7) bond length is 3.12 Å. The Ba(1)-O(8) bond length is 2.86 Å. The Ba(1)-O(9) bond length is 2.72 Å. In the second Ba site, Ba(2) is bonded in a 9-coordinate geometry to one O(1), one O(14), one O(17), one O(2), one O(3), one O(4), one O(6), one O(7), and one O(8) atom. The Ba(2)-O(1) bond length is 2.96 Å. The Ba(2)-O(14) bond length is 2.83 Å. The Ba(2)-O(17) bond length is 2.84 Å. The Ba(2)-O(2) bond length is 2.90 Å. The Ba(2)-O(3) bond length is 2.92 Å. The Ba(2)-O(4) bond length is 3.07 Å. The Ba(2)-O(6) bond length is 2.78 Å. The Ba(2)-O(7) bond length is 2.86 Å. The Ba(2)-O(8) bond length is 2.71 Å. In the third Ba site, Ba(3) is bonded in a 10-coordinate geometry to one O(10), one O(11), one O(13), one O(16), one O(17), one O(4), one O(5), one O(7), and two equivalent O(12) atoms. The Ba(3)-O(10) bond length is 2.79 Å. The Ba(3)-O(11) bond length is 3.04 Å. The Ba(3)-O(13) bond length is 3.03 Å. The Ba(3)-O(16) bond length is 2.81 Å. The Ba(3)-O(17) bond length is 2.83 Å. The Ba(3)-O(4) bond length is 2.91 Å. The Ba(3)-O(5) bond length is 2.82 Å. The Ba(3)-O(7) bond length is 2.91 Å. There is one shorter (2.79 Å) and one longer (2.81 Å) Ba(3)-O(12) bond length. In the fourth Ba site, Ba(4) is bonded in a 4-coordinate geometry to two equivalent O(15) and two equivalent O(18) atoms. Both Ba(4)-O(15) bond lengths are 2.75 Å. Both Ba(4)-O(18) bond lengths are 2.92 Å. There are twelve inequivalent C sites. In the first C site, C(1) is bonded in a distorted bent 120 degrees geometry to one C(2), one O(1), and one O(2) atom. The C(1)-C(2) bond length is 1.47 Å. The C(1)-O(1) bond length is 1.23 Å. The C(1)-O(2) bond length is 1.28 Å. In the second C site, C(2) is bonded in a linear geometry to one C(1) and one C(2) atom. The C(2)-C(2) bond length is 1.24 Å. In the third C site, C(3) is bonded in a distorted bent 120 degrees geometry to one C(4), one O(3), and one O(4) atom. The C(3)-C(4) bond length is 1.48 Å. The C(3)-O(3) bond length is 1.24 Å. The C(3)-O(4) bond length is 1.24 Å. In the fourth C site, C(4) is bonded in a linear geometry to one C(3) and one C(5) atom. The C(4)-C(5) bond length is 1.19 Å. In the fifth C site, C(5) is bonded in a linear geometry to one C(4) and one C(6) atom. The C(5)-C(6) bond length is 1.48 Å. In the sixth C site, C(6) is bonded in a distorted bent 120 degrees geometry to one C(5), one O(5), and one O(6) atom. The C(6)-O(5) bond length is 1.20 Å. The C(6)-O(6) bond length is 1.24 Å. In the seventh C site, C(7) is bonded in a distorted bent 120 degrees geometry to one C(8), one O(7), and one O(8) atom. The C(7)-C(8) bond length is 1.44 Å. The C(7)-O(7) bond length is 1.21 Å. The C(7)-O(8) bond length is 1.27 Å. In the eighth C site, C(8) is bonded in a linear geometry to one C(7) and one C(9) atom. The C(8)-C(9) bond length is 1.18 Å. In the ninth C site, C(9) is bonded in a linear geometry to one C(10) and one C(8) atom. The C(9)-C(10) bond length is 1.47 Å. In the tenth C site, C(10) is bonded in a distorted bent 120 degrees geometry to one C(9), one O(10), and one O(9) atom. The C(10)-O(10) bond length is 1.29 Å. The C(10)-O(9) bond length is 1.26 Å. In the eleventh C site, C(11) is bonded in a distorted bent 120 degrees geometry to one C(12), one O(14), and one O(15) atom. The C(11)-C(12) bond length is 1.49 Å. The C(11)-O(14) bond length is 1.27 Å. The C(11)-O(15) bond length is 1.22 Å. In the twelfth C site, C(12) is bonded in a linear geometry to one C(11) and one C(12) atom. The C(12)-C(12) bond length is 1.19 Å. N(1) is bonded in a trigonal planar geometry to one O(11), one O(12), and one O(13) atom. The N(1)-O(11) bond length is 1.27 Å. The N(1)-O(12) bond length is 1.25 Å. The N(1)-O(13) bond length is 1.24 Å. There are eighteen inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to one Ba(1), one Ba(2), and one C(1) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to one Ba(2) and one C(1) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one Ba(1), one Ba(2), and one C(3) atom. In the fourth O site, O(4) is bonded in a distorted single-bond geometry to one Ba(1), one Ba(2), one Ba(3), and one C(3) atom. In the fifth O site, O(5) is bonded in a distorted single-bond geometry to one Ba(3) and one C(6) atom. In the sixth O site, O(6) is bonded in a distorted single-bond geometry to one Ba(2) and one C(6) atom. In the seventh O site, O(7) is bonded in a single-bond geometry to one Ba(1), one Ba(2), one Ba(3), and one C(7) atom. In the eighth O site, O(8) is bonded in a distorted single-bond geometry to one Ba(1), one Ba(2), and one C(7) atom. In the ninth O site, O(9) is bonded in a distorted single-bond geometry to one Ba(1) and one C(10) atom. In the tenth O site, O(10) is bonded in a distorted single-bond geometry to one Ba(3) and one C(10) atom. In the eleventh O site, O(11) is bonded in a single-bond geometry to one Ba(3) and one N(1) atom. In the twelfth O site, O(12) is bonded in a distorted single-bond geometry to two equivalent Ba(3) and one N(1) atom. In the thirteenth O site, O(13) is bonded in a single-bond geometry to one Ba(3) and one N(1) atom. In the fourteenth O site, O(14) is bonded in a single-bond geometry to one Ba(1), one Ba(2), and one C(11) atom. In the fifteenth O site, O(15) is bonded in a distorted single-bond geometry to one Ba(1), one Ba(4), and one C(11) atom. In the sixteenth O site, O(16) is bonded in a water-like geometry to one Ba(1) and one Ba(3) atom. In the seventeenth O site, O(17) is bonded in a water-like geometry to one Ba(2) and one Ba(3) atom. In the eighteenth O site, O(18) is bonded in a water-like geometry to one Ba(1) and one Ba(4) atom. Linkers: 6 [O]C(=O)C#CC([O])=O. Metal clusters: 7 [Ba]. The MOF has largest included sphere 4.22 A, density 2.38 g/cm3, surface area 2620.86 m2/g, accessible volume 0.13 cm3/g