Mn5P4H8(CO3)8 crystallizes in the triclinic P-1 space group. There are three inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(11), one O(4), one O(6), one O(8), and two equivalent O(9) atoms to form MnO6 octahedra that share corners with three equivalent P(2)CO3 tetrahedra and  an edgeedge with one Mn(1)O6 octahedra. The Mn(1)-O(11) bond length is 2.24 Å. The Mn(1)-O(4) bond length is 2.32 Å. The Mn(1)-O(6) bond length is 2.12 Å. The Mn(1)-O(8) bond length is 2.12 Å. There is one shorter (2.14 Å) and one longer (2.15 Å) Mn(1)-O(9) bond length. In the second Mn site, Mn(2) is bonded to one O(10), one O(12), one O(3), and one O(7) atom to form MnO4 trigonal pyramids that share  a cornercorner with one P(1)CO3 tetrahedra and  a cornercorner with one P(2)CO3 tetrahedra. The Mn(2)-O(10) bond length is 2.23 Å. The Mn(2)-O(12) bond length is 2.17 Å. The Mn(2)-O(3) bond length is 2.04 Å. The Mn(2)-O(7) bond length is 1.99 Å. In the third Mn site, Mn(3) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(5) atoms to form MnO6 octahedra that share corners with four equivalent P(1)CO3 tetrahedra. Both Mn(3)-O(1) bond lengths are 2.14 Å. Both Mn(3)-O(2) bond lengths are 2.23 Å. Both Mn(3)-O(5) bond lengths are 2.17 Å. There are four inequivalent C sites. In the first C site, C(1) is bonded in a 2-coordinate geometry to one P(1), one H(3), and one O(4) atom. The C(1)-P(1) bond length is 1.83 Å. The C(1)-H(3) bond length is 0.97 Å. The C(1)-O(4) bond length is 1.46 Å. In the second C site, C(2) is bonded in a distorted bent 120 degrees geometry to one O(5) and one O(6) atom. The C(2)-O(5) bond length is 1.24 Å. The C(2)-O(6) bond length is 1.24 Å. In the third C site, C(3) is bonded in a 2-coordinate geometry to one C(4), one P(2), one H(4), and one O(10) atom. The C(3)-C(4) bond length is 1.52 Å. The C(3)-P(2) bond length is 1.83 Å. The C(3)-H(4) bond length is 0.98 Å. The C(3)-O(10) bond length is 1.43 Å. In the fourth C site, C(4) is bonded in a distorted trigonal planar geometry to one C(3), one O(11), and one O(12) atom. The C(4)-O(11) bond length is 1.24 Å. The C(4)-O(12) bond length is 1.25 Å. There are two inequivalent P sites. In the first P site, P(1) is bonded to one C(1), one O(1), one O(2), and one O(3) atom to form PCO3 tetrahedra that share corners with two equivalent Mn(3)O6 octahedra and  a cornercorner with one Mn(2)O4 trigonal pyramid. The corner-sharing octahedral tilt angles range from 40-49°. The P(1)-O(1) bond length is 1.52 Å. The P(1)-O(2) bond length is 1.52 Å. The P(1)-O(3) bond length is 1.51 Å. In the second P site, P(2) is bonded to one C(3), one O(7), one O(8), and one O(9) atom to form PCO3 tetrahedra that share corners with three equivalent Mn(1)O6 octahedra and  a cornercorner with one Mn(2)O4 trigonal pyramid. The corner-sharing octahedral tilt angles range from 44-53°. The P(2)-O(7) bond length is 1.51 Å. The P(2)-O(8) bond length is 1.50 Å. The P(2)-O(9) bond length is 1.53 Å. There are four inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one O(4) atom. The H(1)-O(4) bond length is 0.82 Å. In the second H site, H(2) is bonded in a single-bond geometry to one O(10) atom. The H(2)-O(10) bond length is 0.82 Å. In the third H site, H(3) is bonded in a single-bond geometry to one C(1) atom. In the fourth H site, H(4) is bonded in a single-bond geometry to one C(3) atom. There are twelve inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 120 degrees geometry to one Mn(3) and one P(1) atom. In the second O site, O(2) is bonded in a distorted bent 150 degrees geometry to one Mn(3) and one P(1) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Mn(2) and one P(1) atom. In the fourth O site, O(4) is bonded in a 1-coordinate geometry to one Mn(1), one C(1), and one H(1) atom. In the fifth O site, O(5) is bonded in a distorted bent 120 degrees geometry to one Mn(3) and one C(2) atom. In the sixth O site, O(6) is bonded in a bent 120 degrees geometry to one Mn(1) and one C(2) atom. In the seventh O site, O(7) is bonded in a bent 150 degrees geometry to one Mn(2) and one P(2) atom. In the eighth O site, O(8) is bonded in a distorted bent 150 degrees geometry to one Mn(1) and one P(2) atom. In the ninth O site, O(9) is bonded in a distorted trigonal planar geometry to two equivalent Mn(1) and one P(2) atom. In the tenth O site, O(10) is bonded in a distorted trigonal planar geometry to one Mn(2), one C(3), and one H(2) atom. In the eleventh O site, O(11) is bonded in a bent 120 degrees geometry to one Mn(1) and one C(4) atom. In the twelfth O site, O(12) is bonded in a bent 120 degrees geometry to one Mn(2) and one C(4) atom. Linkers: 2 [O]C(=O)[C@@H](O)P([O])([O])=O ,2 [O]C(=O)[C@H](O)P([O])([O])=O. Metal clusters: 5 [Mn]. The MOF has largest included sphere 5.00 A, density 2.01 g/cm3, surface area 2529.98 m2/g, accessible volume 0.16 cm3/g