Cu(CO3)2 crystallizes in the tetragonal P-4n2 space group. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a square co-planar geometry to four equivalent O(1) atoms. All Cu(1)-O(1) bond lengths are 1.97 Å. In the second Cu site, Cu(2) is bonded in a square co-planar geometry to four equivalent O(2) atoms. All Cu(2)-O(2) bond lengths are 1.92 Å. C(1) is bonded in a trigonal planar geometry to one O(1), one O(2), and one O(3) atom. The C(1)-O(1) bond length is 1.27 Å. The C(1)-O(2) bond length is 1.34 Å. The C(1)-O(3) bond length is 1.24 Å. There are three inequivalent O sites. In the first O site, O(1) is bonded in a water-like geometry to one Cu(1) and one C(1) atom. In the second O site, O(2) is bonded in a bent 120 degrees geometry to one Cu(2) and one C(1) atom. In the third O site, O(3) is bonded in a single-bond geometry to one C(1) atom. Linkers: 8 [O]C([O])=O. Metal clusters: 4 [Cu]. The MOF has largest included sphere 5.80 A, density 1.31 g/cm3, surface area 3456.62 m2/g, accessible volume 0.47 cm3/g