Eu2C27H13(NO2)6H2(CN)3 crystallizes in the monoclinic C2/c space group. The structure consists of four 4-methyl-4h-1,2,4-triazole molecules inside a Eu2C27H13(NO2)6 framework. In the Eu2C27H13(NO2)6 framework, Eu(1) is bonded in a 7-coordinate geometry to one N(1), one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom. The Eu(1)-N(1) bond length is 2.58 Å. The Eu(1)-O(1) bond length is 2.39 Å. The Eu(1)-O(2) bond length is 2.47 Å. The Eu(1)-O(3) bond length is 2.50 Å. The Eu(1)-O(4) bond length is 2.40 Å. The Eu(1)-O(5) bond length is 2.30 Å. The Eu(1)-O(6) bond length is 2.33 Å. There are fourteen inequivalent C sites. In the first C site, C(1) is bonded in a distorted bent 120 degrees geometry to one C(3), one O(2), and one O(3) atom. The C(1)-C(3) bond length is 1.53 Å. The C(1)-O(2) bond length is 1.25 Å. The C(1)-O(3) bond length is 1.26 Å. In the second C site, C(2) is bonded in a distorted single-bond geometry to one C(10), one C(3), and one H(1) atom. The C(2)-C(10) bond length is 1.39 Å. The C(2)-C(3) bond length is 1.37 Å. The C(2)-H(1) bond length is 0.93 Å. In the third C site, C(3) is bonded in a trigonal planar geometry to one C(1), one C(2), and one C(7) atom. The C(3)-C(7) bond length is 1.40 Å. In the fourth C site, C(4) is bonded in a distorted single-bond geometry to 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 0.93 Å. In the fifth C site, C(5) is bonded in a trigonal planar geometry to one N(1), one N(2), and one H(3) atom. The C(5)-N(1) bond length is 1.30 Å. The C(5)-N(2) bond length is 1.34 Å. The C(5)-H(3) bond length is 0.93 Å. In the sixth C site, C(6) is bonded in a trigonal planar geometry to one C(11), one C(16), and one C(4) atom. The C(6)-C(11) bond length is 1.51 Å. The C(6)-C(16) bond length is 1.37 Å. In the seventh C site, C(7) is bonded in a distorted single-bond geometry to one C(3) and one H(4) atom. The C(7)-H(4) bond length is 0.93 Å. In the eighth C site, C(8) is bonded in a trigonal planar geometry to one N(2), one N(4), and one H(5) atom. The C(8)-N(2) bond length is 1.35 Å. The C(8)-N(4) bond length is 1.29 Å. The C(8)-H(5) bond length is 0.93 Å. In the ninth C site, C(9) is bonded in a distorted single-bond geometry to one C(10) and one H(6) atom. The C(9)-C(10) bond length is 1.38 Å. The C(9)-H(6) bond length is 0.93 Å. In the tenth C site, C(10) is bonded in a trigonal planar geometry to one C(13), one C(2), and one C(9) atom. The C(10)-C(13) bond length is 1.51 Å. In the eleventh C site, C(11) is bonded in a bent 120 degrees geometry to one C(6), one O(4), and one O(6) atom. The C(11)-O(4) bond length is 1.26 Å. The C(11)-O(6) bond length is 1.25 Å. In the twelfth C site, C(12) is bonded in a distorted single-bond geometry to one N(2) atom. The C(12)-N(2) bond length is 1.44 Å. In the thirteenth C site, C(13) is bonded in a distorted bent 120 degrees geometry to one C(10), one O(1), and one O(5) atom. The C(13)-O(1) bond length is 1.23 Å. The C(13)-O(5) bond length is 1.27 Å. In the fourteenth C site, C(16) is bonded in a distorted single-bond geometry to two equivalent C(6) and one H(8) atom. The C(16)-H(8) bond length is 0.93 Å. There are three inequivalent N sites. In the first N site, N(1) is bonded in a distorted single-bond geometry to one Eu(1), one C(5), and one N(4) atom. The N(1)-N(4) bond length is 1.39 Å. In the second N site, N(2) is bonded in a trigonal planar geometry to one C(12), one C(5), and one C(8) atom. In the third N site, N(4) is bonded in a distorted single-bond geometry to one C(8) and one N(1) atom. There are seven 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 single-bond geometry to one C(5) atom. In the fourth H site, H(4) is bonded in a single-bond geometry to one C(7) atom. In the fifth H site, H(5) is bonded in a single-bond geometry to one C(8) atom. In the sixth H site, H(6) is bonded in a single-bond geometry to one C(9) atom. In the seventh H site, H(8) is bonded in a single-bond geometry to one C(16) atom. There are six inequivalent O sites. In the first O site, O(1) is bonded in a bent 120 degrees geometry to one Eu(1) and one C(13) atom. In the second O site, O(2) is bonded in a distorted L-shaped geometry to one Eu(1) and one C(1) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one Eu(1) and one C(1) atom. In the fourth O site, O(4) is bonded in a distorted bent 120 degrees geometry to one Eu(1) and one C(11) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one Eu(1) and one C(13) atom. In the sixth O site, O(6) is bonded in a distorted bent 150 degrees geometry to one Eu(1) and one C(11) atom. Linkers: 12 [O]C(=O)c1cc(C([O])=O)cc(-n2cnnc2)c1. Metal clusters: 4 [C]1O[Eu]234(O1)O[C]O[Eu]1(O[C]O1)(O[C]O2)(O[C]O3)O[C]O4. RCSR code: pcu. The MOF has largest included sphere 5.60 A, density 1.44 g/cm3, surface area 3221.66 m2/g, accessible volume 0.36 cm3/g