EuC21NH14O10 crystallizes in the monoclinic P2_1/c space group. Eu(1) is bonded in a 8-coordinate geometry to one O(1), one O(10), one O(2), one O(3), one O(6), one O(7), one O(8), and one O(9) atom. The Eu(1)-O(1) bond length is 2.41 Å. The Eu(1)-O(10) bond length is 2.38 Å. The Eu(1)-O(2) bond length is 2.47 Å. The Eu(1)-O(3) bond length is 2.53 Å. The Eu(1)-O(6) bond length is 2.32 Å. The Eu(1)-O(7) bond length is 2.45 Å. The Eu(1)-O(8) bond length is 2.43 Å. The Eu(1)-O(9) bond length is 2.42 Å. There are twenty-one inequivalent C sites. In the first C site, C(18) is bonded in a distorted single-bond geometry to one C(4) and one H(9) atom. The C(18)-C(4) bond length is 1.40 Å. The C(18)-H(9) bond length is 1.09 Å. In the second C site, C(19) is bonded in a distorted bent 120 degrees geometry to one C(4), one O(4), and one O(5) atom. The C(19)-C(4) bond length is 1.50 Å. The C(19)-O(4) bond length is 1.33 Å. The C(19)-O(5) bond length is 1.24 Å. In the third C site, C(20) is bonded in a distorted bent 120 degrees geometry to one C(12), one O(3), and one O(6) atom. The C(20)-C(12) bond length is 1.50 Å. The C(20)-O(3) bond length is 1.28 Å. The C(20)-O(6) bond length is 1.27 Å. In the fourth C site, C(21) is bonded in a distorted bent 120 degrees geometry to one C(16), one O(7), and one O(8) atom. The C(21)-C(16) bond length is 1.49 Å. The C(21)-O(7) bond length is 1.28 Å. The C(21)-O(8) bond length is 1.29 Å. In the fifth C site, C(1) is bonded in a distorted trigonal planar geometry to one C(6), one N(1), and one H(1) atom. The C(1)-C(6) bond length is 1.40 Å. The C(1)-N(1) bond length is 1.34 Å. The C(1)-H(1) bond length is 1.09 Å. In the sixth C site, C(2) is bonded in a distorted single-bond geometry to one C(8) and one H(2) atom. The C(2)-C(8) bond length is 1.40 Å. The C(2)-H(2) bond length is 1.09 Å. In the seventh C site, C(3) is bonded in a distorted trigonal planar geometry to one C(9), one N(1), and one H(3) atom. The C(3)-C(9) bond length is 1.40 Å. The C(3)-N(1) bond length is 1.34 Å. The C(3)-H(3) bond length is 1.09 Å. In the eighth C site, C(4) is bonded in a trigonal planar geometry to one C(15), one C(18), and one C(19) atom. The C(4)-C(15) bond length is 1.40 Å. In the ninth C site, C(5) is bonded in a trigonal planar geometry to one C(10), one C(17), and one C(7) atom. The C(5)-C(10) bond length is 1.42 Å. The C(5)-C(17) bond length is 1.40 Å. The C(5)-C(7) bond length is 1.49 Å. In the tenth C site, C(6) is bonded in a trigonal planar geometry to one C(1), one C(11), and one C(8) atom. The C(6)-C(11) bond length is 1.39 Å. The C(6)-C(8) bond length is 1.47 Å. In the eleventh C site, C(7) is bonded in a distorted bent 120 degrees geometry to one C(5), one O(1), and one O(2) atom. The C(7)-O(1) bond length is 1.29 Å. The C(7)-O(2) bond length is 1.27 Å. In the twelfth C site, C(8) is bonded in a trigonal planar geometry to one C(12), one C(2), and one C(6) atom. The C(8)-C(12) bond length is 1.41 Å. In the thirteenth C site, C(9) is bonded in a trigonal planar geometry to one C(10), one C(11), and one C(3) atom. The C(9)-C(10) bond length is 1.47 Å. The C(9)-C(11) bond length is 1.40 Å. In the fourteenth C site, C(10) is bonded in a trigonal planar geometry to one C(14), one C(5), and one C(9) atom. The C(10)-C(14) bond length is 1.40 Å. In the fifteenth C site, C(11) is bonded in a distorted single-bond geometry to one C(6), one C(9), and one H(4) atom. The C(11)-H(4) bond length is 1.09 Å. In the sixteenth C site, C(12) is bonded in a trigonal planar geometry to one C(15), one C(20), and one C(8) atom. The C(12)-C(15) bond length is 1.40 Å. In the seventeenth C site, C(13) is bonded in a distorted single-bond geometry to one C(16) and one H(5) atom. The C(13)-C(16) bond length is 1.40 Å. The C(13)-H(5) bond length is 1.09 Å. In the eighteenth C site, C(14) is bonded in a distorted single-bond geometry to one C(10) and one H(6) atom. The C(14)-H(6) bond length is 1.09 Å. In the nineteenth C site, C(15) is bonded in a distorted single-bond geometry to one C(12), one C(4), and one H(7) atom. The C(15)-H(7) bond length is 1.09 Å. In the twentieth C site, C(16) is bonded in a trigonal planar geometry to one C(13), one C(17), and one C(21) atom. The C(16)-C(17) bond length is 1.40 Å. In the twenty-first C site, C(17) is bonded in a distorted single-bond geometry to one C(16), one C(5), and one H(8) atom. The C(17)-H(8) bond length is 1.09 Å. N(1) is bonded in a trigonal planar geometry to one C(1), one C(3), and one H(10) atom. The N(1)-H(10) bond length is 1.53 Å. There are fourteen 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(11) atom. In the fifth H site, H(5) is bonded in a single-bond geometry to one C(13) atom. In the sixth H site, H(6) is bonded in a single-bond geometry to one C(14) atom. In the seventh H site, H(7) is bonded in a single-bond geometry to one C(15) atom. In the eighth H site, H(8) is bonded in a single-bond geometry to one C(17) atom. In the ninth H site, H(9) is bonded in a single-bond geometry to one C(18) atom. In the tenth H site, H(10) is bonded in a linear geometry to one N(1) and one O(4) atom. The H(10)-O(4) bond length is 1.07 Å. In the eleventh H site, H(11) is bonded in a single-bond geometry to one O(9) atom. The H(11)-O(9) bond length is 0.97 Å. In the twelfth H site, H(12) is bonded in a distorted single-bond geometry to one O(1) and one O(9) atom. The H(12)-O(1) bond length is 1.67 Å. The H(12)-O(9) bond length is 1.00 Å. In the thirteenth H site, H(13) is bonded in a linear geometry to one O(10) and one O(3) atom. The H(13)-O(10) bond length is 1.01 Å. The H(13)-O(3) bond length is 1.58 Å. In the fourteenth H site, H(14) is bonded in a single-bond geometry to one O(10) atom. The H(14)-O(10) bond length is 0.97 Å. There are ten inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to one Eu(1), one C(7), and one H(12) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to one Eu(1) and one C(7) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Eu(1), one C(20), and one H(13) atom. In the fourth O site, O(4) is bonded in a water-like geometry to one C(19) and one H(10) atom. In the fifth O site, O(5) is bonded in a single-bond geometry to one C(19) atom. In the sixth O site, O(6) is bonded in a 2-coordinate geometry to one Eu(1) and one C(20) atom. In the seventh O site, O(7) is bonded in a distorted L-shaped geometry to one Eu(1) and one C(21) atom. In the eighth O site, O(8) is bonded in a distorted L-shaped geometry to one Eu(1) and one C(21) atom. In the ninth O site, O(9) is bonded in a distorted water-like geometry to one Eu(1), one H(11), and one H(12) atom. In the tenth O site, O(10) is bonded in a distorted water-like geometry to one Eu(1), one H(13), and one H(14) atom. Linkers: 4 [O]C(=O)c1ccc(-c2cncc(-c3ccc(C(=O)O)cc3C([O])=O)c2)c(C([O])=O)c1. Metal clusters: 2 O.O.O.O.O=[C]O[Eu]1(O[C]=O)O[C]O1.O=[C]O[Eu]1(O[C]=O)O[C]O1. RCSR code: sql. The MOF has largest included sphere 3.32 A, density 1.80 g/cm3, surface area 3380.09 m2/g, accessible volume 0.16 cm3/g