Co(HCOO)2 crystallizes in the monoclinic P2_1/c space group. There are four inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(1), one O(11), one O(3), one O(5), one O(7), and one O(9) atom to form a mixture of edge and corner-sharing CoO6 octahedra. The corner-sharing octahedral tilt angles range from 65-67°. The Co(1)-O(1) bond length is 2.09 Å. The Co(1)-O(11) bond length is 2.07 Å. The Co(1)-O(3) bond length is 2.08 Å. The Co(1)-O(5) bond length is 2.12 Å. The Co(1)-O(7) bond length is 2.12 Å. The Co(1)-O(9) bond length is 2.05 Å. In the second Co site, Co(2) is bonded to one O(1), one O(12), one O(2), one O(3), one O(5), and one O(7) atom to form edge-sharing CoO6 octahedra. The Co(2)-O(1) bond length is 2.10 Å. The Co(2)-O(12) bond length is 2.04 Å. The Co(2)-O(2) bond length is 2.05 Å. The Co(2)-O(3) bond length is 2.08 Å. The Co(2)-O(5) bond length is 2.11 Å. The Co(2)-O(7) bond length is 2.12 Å. In the third Co site, Co(3) is bonded to two equivalent O(4), two equivalent O(6), and two equivalent O(9) atoms to form corner-sharing CoO6 octahedra. The corner-sharing octahedral tilt angles are 65°. Both Co(3)-O(4) bond lengths are 2.09 Å. Both Co(3)-O(6) bond lengths are 2.06 Å. Both Co(3)-O(9) bond lengths are 2.11 Å. In the fourth Co site, Co(4) is bonded to two equivalent O(10), two equivalent O(11), and two equivalent O(8) atoms to form corner-sharing CoO6 octahedra. The corner-sharing octahedral tilt angles are 67°. Both Co(4)-O(10) bond lengths are 2.07 Å. Both Co(4)-O(11) bond lengths are 2.11 Å. Both Co(4)-O(8) bond lengths are 2.07 Å. There are six inequivalent C sites. In the first C site, C(1) is bonded in a trigonal planar geometry to one H(1), one O(1), and one O(2) atom. The C(1)-H(1) bond length is 0.95 Å. The C(1)-O(1) bond length is 1.27 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 H(2), one O(3), and one O(4) atom. The C(2)-H(2) bond length is 0.89 Å. The C(2)-O(3) bond length is 1.26 Å. The C(2)-O(4) bond length is 1.23 Å. In the third C site, C(3) is bonded in a trigonal planar geometry to one H(3), one O(5), and one O(6) atom. The C(3)-H(3) bond length is 0.94 Å. The C(3)-O(5) bond length is 1.26 Å. The C(3)-O(6) bond length is 1.23 Å. In the fourth C site, C(4) is bonded in a trigonal planar geometry to one H(6), one O(7), and one O(8) atom. The C(4)-H(6) bond length is 1.00 Å. The C(4)-O(7) bond length is 1.27 Å. The C(4)-O(8) bond length is 1.23 Å. In the fifth C site, C(5) is bonded in a trigonal planar geometry to one H(5), one O(10), and one O(9) atom. The C(5)-H(5) bond length is 0.90 Å. The C(5)-O(10) bond length is 1.22 Å. The C(5)-O(9) bond length is 1.29 Å. In the sixth C site, C(6) is bonded in a trigonal planar geometry to one H(4), one O(11), and one O(12) atom. The C(6)-H(4) bond length is 0.93 Å. The C(6)-O(11) bond length is 1.28 Å. The C(6)-O(12) bond length is 1.23 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(6) atom. In the fifth H site, H(5) is bonded in a single-bond geometry to one C(5) atom. In the sixth H site, H(6) is bonded in a single-bond geometry to one C(4) atom. There are twelve inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Co(1), one Co(2), and one C(1) atom. In the second O site, O(2) is bonded in a bent 120 degrees geometry to one Co(2) and one C(1) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Co(1), one Co(2), and one C(2) atom. In the fourth O site, O(4) is bonded in a distorted bent 120 degrees geometry to one Co(3) and one C(2) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Co(1), one Co(2), and one C(3) atom. In the sixth O site, O(6) is bonded in a distorted bent 120 degrees geometry to one Co(3) and one C(3) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Co(1), one Co(2), and one C(4) atom. In the eighth O site, O(8) is bonded in a distorted bent 120 degrees geometry to one Co(4) and one C(4) atom. In the ninth O site, O(9) is bonded in a trigonal planar geometry to one Co(1), one Co(3), and one C(5) atom. In the tenth O site, O(10) is bonded in a distorted bent 150 degrees geometry to one Co(4) and one C(5) atom. In the eleventh O site, O(11) is bonded in a trigonal planar geometry to one Co(1), one Co(4), and one C(6) atom. In the twelfth O site, O(12) is bonded in a bent 120 degrees geometry to one Co(2) and one C(6) atom. Linkers: 24 [O]C=O. Metal clusters: 12 [Co]. The MOF has largest included sphere 4.60 A, density 1.86 g/cm3, surface area 2470.57 m2/g, accessible volume 0.25 cm3/g