Zn2C18PH12(NO3)4(C3H2)4 crystallizes in the monoclinic C2/c space group. The structure consists of eight 2,3-dimethyl-1,3-butadiene molecules inside a Zn2C18PH12(NO3)4 framework. In the Zn2C18PH12(NO3)4 framework, Zn(1) is bonded to one N(1), one O(1), one O(2), and one O(3) atom to form ZnNO3 tetrahedra that share corners with two equivalent P(1)O4 tetrahedra. The Zn(1)-N(1) bond length is 2.03 Å. The Zn(1)-O(1) bond length is 1.94 Å. The Zn(1)-O(2) bond length is 1.92 Å. The Zn(1)-O(3) bond length is 1.96 Å. There are nine inequivalent C sites. In the first C site, C(1) is bonded in a distorted single-bond geometry to one C(2), one C(3), and one H(1) atom. The C(1)-C(2) bond length is 1.38 Å. The C(1)-C(3) bond length is 1.38 Å. The C(1)-H(1) bond length is 1.03 Å. In the second C site, C(2) is bonded in a trigonal planar geometry to one C(1), one C(3), and one C(4) atom. The C(2)-C(3) bond length is 1.40 Å. The C(2)-C(4) bond length is 1.51 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(5) atom. The C(3)-C(5) bond length is 1.50 Å. In the fourth C site, C(4) is bonded in a distorted bent 120 degrees geometry to one C(2), one O(3), and one O(4) atom. The C(4)-O(3) bond length is 1.27 Å. The C(4)-O(4) bond length is 1.22 Å. In the fifth C site, C(5) is bonded in a distorted bent 120 degrees geometry to one C(3), one O(5), and one O(6) atom. The C(5)-O(5) bond length is 1.30 Å. The C(5)-O(6) bond length is 1.21 Å. In the sixth C site, C(6) is bonded in a distorted bent 120 degrees geometry to one N(1) and one H(2) atom. The C(6)-N(1) bond length is 1.34 Å. The C(6)-H(2) bond length is 0.96 Å. In the seventh C site, C(10) is bonded in a distorted bent 120 degrees geometry to one N(1) and one H(5) atom. The C(10)-N(1) bond length is 1.33 Å. The C(10)-H(5) bond length is 0.97 Å. In the eighth C site, C(13) is bonded in a distorted bent 120 degrees geometry to one N(2) and one H(7) atom. The C(13)-N(2) bond length is 1.31 Å. The C(13)-H(7) bond length is 0.97 Å. In the ninth C site, C(14) is bonded in a distorted bent 120 degrees geometry to one N(2) and one H(8) atom. The C(14)-N(2) bond length is 1.31 Å. The C(14)-H(8) bond length is 0.98 Å. P(1) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form PO4 tetrahedra that share corners with four equivalent Zn(1)NO3 tetrahedra. Both P(1)-O(1) bond lengths are 1.53 Å. Both P(1)-O(2) bond lengths are 1.52 Å. There are two inequivalent N sites. In the first N site, N(1) is bonded in a trigonal planar geometry to one Zn(1), one C(10), and one C(6) atom. In the second N site, N(2) is bonded in a trigonal planar geometry to one C(13), one C(14), and one H(10) atom. The N(2)-H(10) bond length is 0.92 Å. 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(6) atom. In the third H site, H(5) is bonded in a single-bond geometry to one C(10) atom. In the fourth H site, H(7) is bonded in a single-bond geometry to one C(13) atom. In the fifth H site, H(8) is bonded in a single-bond geometry to one C(14) atom. In the sixth H site, H(10) is bonded in a distorted linear geometry to one N(2) and one O(5) atom. The H(10)-O(5) bond length is 1.68 Å. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 120 degrees geometry to one Zn(1) and one P(1) atom. In the second O site, O(2) is bonded in a bent 120 degrees geometry to one Zn(1) and one P(1) atom. In the third O site, O(3) is bonded in a bent 120 degrees geometry to one Zn(1) and one C(4) atom. In the fourth O site, O(4) is bonded in a single-bond geometry to one C(4) atom. In the fifth O site, O(5) is bonded in a distorted bent 120 degrees geometry to one C(5) and one H(10) atom. In the sixth O site, O(6) is bonded in a single-bond geometry to one C(5) atom. Linkers: 4 [O]C(=O)c1cc(C([O])=O)c(C([O])=O)cc1C([O])=O. Metal clusters: 8 [Zn]. The MOF has largest included sphere 5.77 A, density 1.29 g/cm3, surface area 4437.14 m2/g, accessible volume 0.32 cm3/g