Zn2H8(CO)9 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 distorted octahedral geometry to one O(1), one O(2), one O(3), one O(4), one O(7), and one O(9) atom. The Zn(1)-O(1) bond length is 2.06 Å. The Zn(1)-O(2) bond length is 2.03 Å. The Zn(1)-O(3) bond length is 2.15 Å. The Zn(1)-O(4) bond length is 2.20 Å. The Zn(1)-O(7) bond length is 2.06 Å. The Zn(1)-O(9) bond length is 2.33 Å. In the second Zn site, Zn(2) is bonded in a 6-coordinate geometry to one O(3), one O(5), one O(6), one O(8), and two equivalent O(1) atoms. The Zn(2)-O(3) bond length is 2.54 Å. The Zn(2)-O(5) bond length is 2.03 Å. The Zn(2)-O(6) bond length is 2.11 Å. The Zn(2)-O(8) bond length is 2.12 Å. There is one shorter (2.07 Å) and one longer (2.11 Å) Zn(2)-O(1) bond length. There are nine inequivalent C sites. In the first C site, C(1) is bonded in a trigonal planar geometry to one C(5), one C(7), and one C(9) atom. The C(1)-C(5) bond length is 1.40 Å. The C(1)-C(7) bond length is 1.40 Å. The C(1)-C(9) bond length is 1.50 Å. In the second C site, C(2) is bonded in a trigonal planar geometry to one C(3), one C(4), and one C(5) atom. The C(2)-C(3) bond length is 1.41 Å. The C(2)-C(4) bond length is 1.50 Å. The C(2)-C(5) bond length is 1.40 Å. In the third C site, C(3) is bonded in a trigonal planar geometry to one C(2), one C(6), and one C(8) atom. The C(3)-C(6) bond length is 1.40 Å. The C(3)-C(8) 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(6), and one O(7) atom. The C(4)-O(6) bond length is 1.26 Å. The C(4)-O(7) bond length is 1.29 Å. In the fifth C site, C(5) is bonded in a distorted trigonal planar geometry to one C(1), one C(2), and one H(3) atom. The C(5)-H(3) bond length is 1.09 Å. In the sixth C site, C(6) is bonded in a distorted single-bond geometry to one C(3) and one H(4) atom. The C(6)-H(4) bond length is 1.09 Å. In the seventh C site, C(7) is bonded in a distorted single-bond geometry to one C(1) and one H(5) atom. The C(7)-H(5) bond length is 1.09 Å. In the eighth C site, C(8) is bonded in a distorted bent 120 degrees geometry to one C(3), one O(3), and one O(9) atom. The C(8)-O(3) bond length is 1.27 Å. The C(8)-O(9) bond length is 1.28 Å. In the ninth C site, C(9) is bonded in a distorted bent 120 degrees geometry to one C(1), one O(2), and one O(5) atom. The C(9)-O(2) bond length is 1.28 Å. The C(9)-O(5) bond length is 1.27 Å. There are eight inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one O(4) and one O(7) atom. The H(1)-O(4) bond length is 1.00 Å. The H(1)-O(7) bond length is 1.71 Å. In the second H site, H(2) is bonded in a single-bond geometry to one O(4) atom. The H(2)-O(4) bond length is 0.98 Å. 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(6) atom. In the fifth H site, H(5) is bonded in a single-bond geometry to one C(7) atom. In the sixth H site, H(6) is bonded in a linear geometry to one O(8) and one O(9) atom. The H(6)-O(8) bond length is 1.02 Å. The H(6)-O(9) bond length is 1.57 Å. In the seventh H site, H(7) is bonded in a single-bond geometry to one O(8) atom. The H(7)-O(8) bond length is 0.98 Å. In the eighth H site, H(8) is bonded in a single-bond geometry to one O(1) atom. The H(8)-O(1) bond length is 0.97 Å. There are nine inequivalent O sites. In the first O site, O(1) is bonded to one Zn(1), two equivalent Zn(2), and one H(8) atom to form distorted edge-sharing OZn3H tetrahedra. In the second O site, O(2) is bonded in a distorted bent 120 degrees geometry to one Zn(1) and one C(9) atom. In the third O site, O(3) is bonded in a 2-coordinate geometry to one Zn(1), one Zn(2), and one C(8) atom. In the fourth O site, O(4) is bonded in a water-like geometry to one Zn(1), one H(1), and one H(2) atom. In the fifth O site, O(5) is bonded in a bent 120 degrees geometry to one Zn(2) and one C(9) atom. In the sixth O site, O(6) is bonded in a distorted bent 120 degrees geometry to one Zn(2) and one C(4) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Zn(1), one C(4), and one H(1) atom. In the eighth O site, O(8) is bonded in a distorted water-like geometry to one Zn(2), one H(6), and one H(7) atom. In the ninth O site, O(9) is bonded in a 3-coordinate geometry to one Zn(1), one C(8), and one H(6) atom. Linkers: 2 [O]C(=O)c1ccc(C([O])=O)c(C([O])=O)c1. Metal clusters: 4 [Zn]. The MOF has largest included sphere 3.82 A, density 2.16 g/cm3, surface area 2779.76 m2/g, accessible volume 0.08 cm3/g