NiC17P2H18(NO2)4C3H2 crystallizes in the monoclinic C2/c space group. The structure consists of four 2,3-dimethyl-1,3-butadiene molecules inside a NiC17P2H18(NO2)4 framework. In the NiC17P2H18(NO2)4 framework, there are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to two equivalent N(1), two equivalent N(2), and two equivalent O(1) atoms to form NiN4O2 octahedra that share corners with two equivalent P(1)O4 tetrahedra. Both Ni(1)-N(1) bond lengths are 2.04 Å. Both Ni(1)-N(2) bond lengths are 2.06 Å. Both Ni(1)-O(1) bond lengths are 2.29 Å. In the second Ni site, Ni(2) is bonded to two equivalent N(3), two equivalent N(4), and two equivalent O(5) atoms to form NiN4O2 octahedra that share corners with two equivalent P(2)O4 tetrahedra. Both Ni(2)-N(3) bond lengths are 2.01 Å. Both Ni(2)-N(4) bond lengths are 2.07 Å. Both Ni(2)-O(5) bond lengths are 2.15 Å. There are seventeen inequivalent C sites. In the first C site, C(19) is bonded in a distorted single-bond geometry to one C(18) and one H(17) atom. The C(19)-C(18) bond length is 1.40 Å. The C(19)-H(17) bond length is 1.09 Å. In the second C site, C(20) is bonded in a distorted bent 120 degrees geometry to one N(4) and one H(18) atom. The C(20)-N(4) bond length is 1.35 Å. The C(20)-H(18) bond length is 1.09 Å. In the third C site, C(1) is bonded in a distorted bent 120 degrees geometry to one C(2), one N(2), and one H(1) atom. The C(1)-C(2) bond length is 1.39 Å. The C(1)-N(2) bond length is 1.35 Å. The C(1)-H(1) bond length is 1.09 Å. In the fourth C site, C(2) is bonded in a distorted trigonal planar geometry to one C(1), one C(3), and one H(2) atom. The C(2)-C(3) bond length is 1.40 Å. The C(2)-H(2) bond length is 1.09 Å. In the fifth C site, C(3) is bonded in a trigonal planar geometry to one C(2), one C(4), and one C(8) atom. The C(3)-C(4) bond length is 1.40 Å. The C(3)-C(8) bond length is 1.47 Å. In the sixth C site, C(4) is bonded in a distorted single-bond geometry to one C(3) and one H(3) atom. The C(4)-H(3) bond length is 1.09 Å. In the seventh C site, C(5) is bonded in a distorted bent 120 degrees geometry to one N(2) and one H(4) atom. The C(5)-N(2) bond length is 1.35 Å. The C(5)-H(4) bond length is 1.09 Å. In the eighth C site, C(6) is bonded in a distorted bent 120 degrees geometry to one N(1) and one H(5) atom. The C(6)-N(1) bond length is 1.35 Å. The C(6)-H(5) bond length is 1.09 Å. In the ninth C site, C(7) is bonded in a distorted single-bond geometry to one C(8) and one H(6) atom. The C(7)-C(8) bond length is 1.40 Å. The C(7)-H(6) bond length is 1.09 Å. In the tenth C site, C(8) is bonded in a trigonal planar geometry to one C(3), one C(7), and one C(9) atom. The C(8)-C(9) bond length is 1.40 Å. In the eleventh C site, C(9) is bonded in a distorted single-bond geometry to one C(8) and one H(7) atom. The C(9)-H(7) bond length is 1.09 Å. In the twelfth C site, C(10) is bonded in a distorted bent 120 degrees geometry to one N(1) and one H(8) atom. The C(10)-N(1) bond length is 1.35 Å. The C(10)-H(8) bond length is 1.09 Å. In the thirteenth C site, C(11) is bonded in a distorted bent 120 degrees geometry to one N(3) and one H(11) atom. The C(11)-N(3) bond length is 1.34 Å. The C(11)-H(11) bond length is 1.08 Å. In the fourteenth C site, C(15) is bonded in a distorted bent 120 degrees geometry to one N(3) and one H(14) atom. The C(15)-N(3) bond length is 1.35 Å. The C(15)-H(14) bond length is 1.09 Å. In the fifteenth C site, C(16) is bonded in a distorted bent 120 degrees geometry to one C(17), one N(4), and one H(15) atom. The C(16)-C(17) bond length is 1.39 Å. The C(16)-N(4) bond length is 1.35 Å. The C(16)-H(15) bond length is 1.09 Å. In the sixteenth C site, C(17) is bonded in a distorted trigonal planar geometry to one C(16), one C(18), and one H(16) atom. The C(17)-C(18) bond length is 1.40 Å. The C(17)-H(16) bond length is 1.09 Å. In the seventeenth C site, C(18) is bonded in a trigonal planar geometry to one C(17), one C(18), and one C(19) atom. The C(18)-C(18) bond length is 1.47 Å. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form PO4 tetrahedra that share  a cornercorner with one Ni(1)N4O2 octahedra. The corner-sharing octahedral tilt angles are 2°. The P(1)-O(1) bond length is 1.52 Å. The P(1)-O(2) bond length is 1.62 Å. The P(1)-O(3) bond length is 1.60 Å. The P(1)-O(4) bond length is 1.53 Å. In the second P site, P(2) is bonded to one O(5), one O(6), one O(7), and one O(8) atom to form PO4 tetrahedra that share  a cornercorner with one Ni(2)N4O2 octahedra. The corner-sharing octahedral tilt angles are 11°. The P(2)-O(5) bond length is 1.51 Å. The P(2)-O(6) bond length is 1.60 Å. The P(2)-O(7) bond length is 1.61 Å. The P(2)-O(8) bond length is 1.53 Å. There are four inequivalent N sites. In the first N site, N(1) is bonded in a trigonal planar geometry to one Ni(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 Ni(1), one C(1), and one C(5) atom. In the third N site, N(3) is bonded in a trigonal planar geometry to one Ni(2), one C(11), and one C(15) atom. In the fourth N site, N(4) is bonded in a trigonal planar geometry to one Ni(2), one C(16), and one C(20) atom. There are eighteen 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(4) atom. In the fourth H site, H(4) is bonded in a single-bond geometry to one C(5) atom. In the fifth H site, H(5) is bonded in a single-bond geometry to one C(6) atom. In the sixth H site, H(6) is bonded in a single-bond geometry to one C(7) atom. In the seventh H site, H(7) is bonded in a single-bond geometry to one C(9) atom. In the eighth H site, H(8) is bonded in a single-bond geometry to one C(10) atom. In the ninth H site, H(9) is bonded in a single-bond geometry to one O(3) atom. The H(9)-O(3) bond length is 1.01 Å. In the tenth H site, H(10) is bonded in a single-bond geometry to one O(2) atom. The H(10)-O(2) bond length is 1.00 Å. In the eleventh H site, H(11) is bonded in a single-bond geometry to one C(11) atom. In the twelfth H site, H(14) is bonded in a single-bond geometry to one C(15) atom. In the thirteenth H site, H(15) is bonded in a single-bond geometry to one C(16) atom. In the fourteenth H site, H(16) is bonded in a single-bond geometry to one C(17) atom. In the fifteenth H site, H(17) is bonded in a single-bond geometry to one C(19) atom. In the sixteenth H site, H(18) is bonded in a single-bond geometry to one C(20) atom. In the seventeenth H site, H(19) is bonded in a linear geometry to one O(6) and one O(8) atom. The H(19)-O(6) bond length is 1.03 Å. The H(19)-O(8) bond length is 1.53 Å. In the eighteenth H site, H(20) is bonded in a single-bond geometry to one O(4) and one O(7) atom. The H(20)-O(4) bond length is 1.71 Å. The H(20)-O(7) bond length is 1.01 Å. There are eight inequivalent O sites. In the first O site, O(3) is bonded in a bent 120 degrees geometry to one P(1) and one H(9) atom. In the second O site, O(4) is bonded in a distorted water-like geometry to one P(1) and one H(20) atom. In the third O site, O(5) is bonded in a distorted linear geometry to one Ni(2) and one P(2) atom. In the fourth O site, O(6) is bonded in a water-like geometry to one P(2) and one H(19) atom. In the fifth O site, O(7) is bonded in a bent 120 degrees geometry to one P(2) and one H(20) atom. In the sixth O site, O(8) is bonded in a distorted bent 120 degrees geometry to one P(2) and one H(19) atom. In the seventh O site, O(2) is bonded in a bent 120 degrees geometry to one P(1) and one H(10) atom. In the eighth O site, O(1) is bonded in a distorted linear geometry to one Ni(1) and one P(1) atom. Linkers: 1 c1cc(-c2ccncc2)ccn1. Metal clusters: 2 [Ni]. The MOF has largest included sphere 4.59 A, density 1.39 g/cm3, surface area 4211.52 m2/g, accessible volume 0.29 cm3/g