CrMn(CO2)6 crystallizes in the orthorhombic P2_12_12_1 space group. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded in an octahedral geometry to one O(15), one O(16), one O(19), one O(20), one O(23), and one O(24) atom. The Cr(1)-O(15) bond length is 1.97 Å. The Cr(1)-O(16) bond length is 1.98 Å. The Cr(1)-O(19) bond length is 1.97 Å. The Cr(1)-O(20) bond length is 1.97 Å. The Cr(1)-O(23) bond length is 1.98 Å. The Cr(1)-O(24) bond length is 1.97 Å. In the second Cr site, Cr(2) is bonded in an octahedral geometry to one O(1), one O(10), one O(2), one O(5), one O(6), and one O(9) atom. The Cr(2)-O(1) bond length is 1.98 Å. The Cr(2)-O(10) bond length is 1.98 Å. The Cr(2)-O(2) bond length is 1.96 Å. The Cr(2)-O(5) bond length is 1.96 Å. The Cr(2)-O(6) bond length is 1.97 Å. The Cr(2)-O(9) bond length is 1.96 Å. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded in an octahedral geometry to one O(11), one O(12), one O(13), one O(14), one O(17), and one O(18) atom. The Mn(1)-O(11) bond length is 2.17 Å. The Mn(1)-O(12) bond length is 2.21 Å. The Mn(1)-O(13) bond length is 2.17 Å. The Mn(1)-O(14) bond length is 2.17 Å. The Mn(1)-O(17) bond length is 2.17 Å. The Mn(1)-O(18) bond length is 2.15 Å. In the second Mn site, Mn(2) is bonded in an octahedral geometry to one O(21), one O(22), one O(3), one O(4), one O(7), and one O(8) atom. The Mn(2)-O(21) bond length is 2.16 Å. The Mn(2)-O(22) bond length is 2.18 Å. The Mn(2)-O(3) bond length is 2.20 Å. The Mn(2)-O(4) bond length is 2.18 Å. The Mn(2)-O(7) bond length is 2.19 Å. The Mn(2)-O(8) bond length is 2.21 Å. There are twelve inequivalent C sites. In the first C site, C(1) is bonded in a distorted bent 120 degrees geometry to one O(1) and one O(3) atom. The C(1)-O(1) bond length is 1.28 Å. The C(1)-O(3) bond length is 1.22 Å. In the second C site, C(2) is bonded in a distorted bent 120 degrees geometry to one O(2) and one O(4) atom. The C(2)-O(2) bond length is 1.27 Å. The C(2)-O(4) bond length is 1.23 Å. In the third C site, C(3) is bonded in a distorted bent 120 degrees geometry to one O(5) and one O(7) atom. The C(3)-O(5) bond length is 1.26 Å. The C(3)-O(7) bond length is 1.26 Å. In the fourth C site, C(4) is bonded in a distorted bent 120 degrees geometry to one O(6) and one O(8) atom. The C(4)-O(6) bond length is 1.26 Å. The C(4)-O(8) bond length is 1.24 Å. In the fifth C site, C(5) is bonded in a distorted bent 120 degrees geometry to one O(11) and one O(9) atom. The C(5)-O(11) bond length is 1.23 Å. The C(5)-O(9) bond length is 1.26 Å. In the sixth C site, C(6) is bonded in a distorted bent 120 degrees geometry to one O(10) and one O(12) atom. The C(6)-O(10) bond length is 1.26 Å. The C(6)-O(12) bond length is 1.23 Å. In the seventh C site, C(7) is bonded in a distorted bent 120 degrees geometry to one O(13) and one O(15) atom. The C(7)-O(13) bond length is 1.21 Å. The C(7)-O(15) bond length is 1.28 Å. In the eighth C site, C(8) is bonded in a distorted bent 120 degrees geometry to one O(14) and one O(16) atom. The C(8)-O(14) bond length is 1.22 Å. The C(8)-O(16) bond length is 1.27 Å. In the ninth C site, C(9) is bonded in a distorted bent 120 degrees geometry to one O(17) and one O(19) atom. The C(9)-O(17) bond length is 1.22 Å. The C(9)-O(19) bond length is 1.28 Å. In the tenth C site, C(10) is bonded in a distorted bent 120 degrees geometry to one O(18) and one O(20) atom. The C(10)-O(18) bond length is 1.23 Å. The C(10)-O(20) bond length is 1.30 Å. In the eleventh C site, C(11) is bonded in a distorted bent 120 degrees geometry to one O(21) and one O(23) atom. The C(11)-O(21) bond length is 1.23 Å. The C(11)-O(23) bond length is 1.26 Å. In the twelfth C site, C(12) is bonded in a distorted bent 120 degrees geometry to one O(22) and one O(24) atom. The C(12)-O(22) bond length is 1.22 Å. The C(12)-O(24) bond length is 1.28 Å. There are twenty-four inequivalent O sites. In the first O site, O(1) is bonded in a water-like geometry to one Cr(2) and one C(1) atom. In the second O site, O(2) is bonded in a bent 120 degrees geometry to one Cr(2) and one C(2) atom. In the third O site, O(3) is bonded in a bent 120 degrees geometry to one Mn(2) and one C(1) atom. In the fourth O site, O(4) is bonded in a bent 120 degrees geometry to one Mn(2) and one C(2) atom. In the fifth O site, O(5) is bonded in a bent 120 degrees geometry to one Cr(2) and one C(3) atom. In the sixth O site, O(6) is bonded in a bent 120 degrees geometry to one Cr(2) and one C(4) atom. In the seventh O site, O(7) is bonded in a bent 120 degrees geometry to one Mn(2) and one C(3) atom. In the eighth O site, O(8) is bonded in a bent 120 degrees geometry to one Mn(2) and one C(4) atom. In the ninth O site, O(9) is bonded in a bent 120 degrees geometry to one Cr(2) and one C(5) atom. In the tenth O site, O(10) is bonded in a bent 120 degrees geometry to one Cr(2) and one C(6) atom. In the eleventh O site, O(11) is bonded in a bent 120 degrees geometry to one Mn(1) and one C(5) atom. In the twelfth O site, O(12) is bonded in a bent 120 degrees geometry to one Mn(1) and one C(6) atom. In the thirteenth O site, O(13) is bonded in a bent 120 degrees geometry to one Mn(1) and one C(7) atom. In the fourteenth O site, O(14) is bonded in a bent 120 degrees geometry to one Mn(1) and one C(8) atom. In the fifteenth O site, O(15) is bonded in a bent 120 degrees geometry to one Cr(1) and one C(7) atom. In the sixteenth O site, O(16) is bonded in a bent 120 degrees geometry to one Cr(1) and one C(8) atom. In the seventeenth O site, O(17) is bonded in a bent 120 degrees geometry to one Mn(1) and one C(9) atom. In the eighteenth O site, O(18) is bonded in a water-like geometry to one Mn(1) and one C(10) atom. In the nineteenth O site, O(19) is bonded in a bent 120 degrees geometry to one Cr(1) and one C(9) atom. In the twentieth O site, O(20) is bonded in a water-like geometry to one Cr(1) and one C(10) atom. In the twenty-first O site, O(21) is bonded in a bent 120 degrees geometry to one Mn(2) and one C(11) atom. In the twenty-second O site, O(22) is bonded in a water-like geometry to one Mn(2) and one C(12) atom. In the twenty-third O site, O(23) is bonded in a bent 120 degrees geometry to one Cr(1) and one C(11) atom. In the twenty-fourth O site, O(24) is bonded in a bent 120 degrees geometry to one Cr(1) and one C(12) atom. Linkers: 24 [O]C(=O)C([O])=O. Metal clusters: 8 [Mn] ,8 [Cr]. The MOF has largest included sphere 9.02 A, density 0.71 g/cm3, surface area 3356.10 m2/g, accessible volume 1.06 cm3/g