Yb(CO2)4 crystallizes in the tetragonal I4_1/a space group. Yb(1) is bonded in a 8-coordinate geometry to four equivalent O(1) and four equivalent O(2) atoms. All Yb(1)-O(1) bond lengths are 2.38 Å. All Yb(1)-O(2) bond lengths are 2.30 Å. C(1) is bonded in a distorted bent 120 degrees geometry to one O(1) and one O(2) atom. The C(1)-O(1) bond length is 1.25 Å. The C(1)-O(2) bond length is 1.25 Å. There are two inequivalent O sites. In the first O site, O(2) is bonded in a bent 120 degrees geometry to one Yb(1) and one C(1) atom. In the second O site, O(1) is bonded in a bent 120 degrees geometry to one Yb(1) and one C(1) atom. Linkers: 8 [O]C(=O)C([O])=O. Metal clusters: 4 [Yb]. RCSR code: jeb. The MOF has largest included sphere 5.01 A, density 1.86 g/cm3, surface area 2054.64 m2/g, accessible volume 0.27 cm3/g