GaC8H5O5 crystallizes in the monoclinic C2/c space group. Ga(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form corner-sharing GaO6 octahedra. The corner-sharing octahedral tilt angles are 55°. Both Ga(1)-O(1) bond lengths are 2.00 Å. Both Ga(1)-O(2) bond lengths are 1.99 Å. Both Ga(1)-O(3) bond lengths are 1.89 Å. There are four inequivalent C sites. In the first C site, C(1) is bonded in a distorted bent 120 degrees geometry to one C(2), one O(1), and one O(2) atom. The C(1)-C(2) bond length is 1.55 Å. The C(1)-O(1) bond length is 1.19 Å. The C(1)-O(2) bond length is 1.24 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 1.35 Å. The C(2)-C(4) bond length is 1.36 Å. In the third C site, C(3) is bonded in a distorted trigonal planar geometry to one C(2), one C(4), and one H(2) atom. The C(3)-C(4) bond length is 1.40 Å. The C(3)-H(2) bond length is 1.07 Å. In the fourth C site, C(4) is bonded in a distorted trigonal planar geometry to one C(2), one C(3), and one H(1) atom. The C(4)-H(1) bond length is 1.08 Å. There are three inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one C(4) atom. In the second H site, H(2) is bonded in a single-bond geometry to one C(3) atom. In the third H site, H(3) is bonded in a single-bond geometry to one O(3) atom. The H(3)-O(3) bond length is 1.00 Å. There are three inequivalent O sites. In the first O site, O(3) is bonded in a trigonal planar geometry to two equivalent Ga(1) and one H(3) atom. In the second O site, O(1) is bonded in a bent 120 degrees geometry to one Ga(1) and one C(1) atom. In the third O site, O(2) is bonded in a bent 120 degrees geometry to one Ga(1) and one C(1) atom. Linkers: 4 [O]C(=O)c1ccc(C([O])=O)cc1. Metal clusters: 4 [Ga]. The MOF has largest included sphere 6.01 A, density 1.23 g/cm3, surface area 3344.99 m2/g, accessible volume 0.47 cm3/g