Zn2C4N8H6O7 crystallizes in the triclinic P-1 space group. There are two inequivalent Zn sites. In the first Zn site, Zn(1) is bonded in a tetrahedral geometry to one N(2), one N(3), one N(4), and one O(1) atom. The Zn(1)-N(2) bond length is 1.99 Å. The Zn(1)-N(3) bond length is 1.98 Å. The Zn(1)-N(4) bond length is 1.99 Å. The Zn(1)-O(1) bond length is 2.02 Å. In the second Zn site, Zn(2) is bonded in an octahedral geometry to one N(1), one N(5), one N(6), one O(4), one O(5), and one O(7) atom. The Zn(2)-N(1) bond length is 2.09 Å. The Zn(2)-N(5) bond length is 2.06 Å. The Zn(2)-N(6) bond length is 2.07 Å. The Zn(2)-O(4) bond length is 2.31 Å. The Zn(2)-O(5) bond length is 2.29 Å. The Zn(2)-O(7) bond length is 2.15 Å. There are four inequivalent C sites. In the first C site, C(1) is bonded in a trigonal planar geometry to one N(1), one N(2), and one H(1) atom. The C(1)-N(1) bond length is 1.35 Å. The C(1)-N(2) bond length is 1.33 Å. The C(1)-H(1) bond length is 1.09 Å. In the second C site, C(2) is bonded in a trigonal planar geometry to one N(1), one N(3), and one H(2) atom. The C(2)-N(1) bond length is 1.35 Å. The C(2)-N(3) bond length is 1.33 Å. The C(2)-H(2) bond length is 1.09 Å. In the third C site, C(3) is bonded in a trigonal planar geometry to one N(4), one N(5), and one H(3) atom. The C(3)-N(4) bond length is 1.36 Å. The C(3)-N(5) bond length is 1.33 Å. The C(3)-H(3) bond length is 1.09 Å. In the fourth C site, C(4) is bonded in a trigonal planar geometry to one N(4), one N(6), and one H(4) atom. The C(4)-N(4) bond length is 1.35 Å. The C(4)-N(6) bond length is 1.33 Å. The C(4)-H(4) bond length is 1.08 Å. There are eight inequivalent N sites. In the first N site, N(1) is bonded in a trigonal planar geometry to one Zn(2), one C(1), and one C(2) atom. In the second N site, N(2) is bonded in a distorted trigonal planar geometry to one Zn(1), one C(1), and one N(3) atom. The N(2)-N(3) bond length is 1.37 Å. In the third N site, N(3) is bonded in a distorted trigonal planar geometry to one Zn(1), one C(2), and one N(2) atom. In the fourth N site, N(4) is bonded in a trigonal planar geometry to one Zn(1), one C(3), and one C(4) atom. In the fifth N site, N(5) is bonded in a distorted trigonal planar geometry to one Zn(2), one C(3), and one N(6) atom. The N(5)-N(6) bond length is 1.37 Å. In the sixth N site, N(6) is bonded in a distorted trigonal planar geometry to one Zn(2), one C(4), and one N(5) atom. In the seventh N site, N(7) is bonded in a trigonal planar geometry to one O(1), one O(2), and one O(3) atom. The N(7)-O(1) bond length is 1.31 Å. The N(7)-O(2) bond length is 1.26 Å. The N(7)-O(3) bond length is 1.24 Å. In the eighth N site, N(8) is bonded in a trigonal planar geometry to one O(4), one O(5), and one O(6) atom. The N(8)-O(4) bond length is 1.30 Å. The N(8)-O(5) bond length is 1.27 Å. The N(8)-O(6) bond length is 1.24 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(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(4) atom. In the fifth H site, H(5) is bonded in a single-bond geometry to one O(7) atom. The H(5)-O(7) bond length is 0.99 Å. In the sixth H site, H(6) is bonded in a single-bond geometry to one O(4) and one O(7) atom. The H(6)-O(4) bond length is 1.75 Å. The H(6)-O(7) bond length is 0.99 Å. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a bent 120 degrees geometry to one Zn(1) and one N(7) atom. In the second O site, O(2) is bonded in a single-bond geometry to one N(7) atom. In the third O site, O(3) is bonded in a single-bond geometry to one N(7) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Zn(2), one N(8), and one H(6) atom. In the fifth O site, O(5) is bonded in an L-shaped geometry to one Zn(2) and one N(8) atom. In the sixth O site, O(6) is bonded in a single-bond geometry to one N(8) atom. In the seventh O site, O(7) is bonded in a distorted water-like geometry to one Zn(2), one H(5), and one H(6) atom. Linkers: 2 C1=NC=N[N]1 ,2 [N]1=CN=NC=1. Metal clusters: 1 O=[N+]([O-])O[Zn]1=NN=[Zn](O[N+](=O)[O-])N=N1 ,1 O.O.[O]N1O[Zn]2(N=N[Zn]3(N=N2)ON([O])O3)O1. The MOF has largest included sphere 1.85 A, density 2.23 g/cm3, surface area 3601.85 m2/g, accessible volume 0.12 cm3/g