KV2C3P2O8 crystallizes in the monoclinic C2/c space group. K(1) is bonded in a 5-coordinate geometry to one O(1), one O(2), one O(3), one O(4), and one O(7) atom. The K(1)-O(1) bond length is 2.95 Å. The K(1)-O(2) bond length is 3.09 Å. The K(1)-O(3) bond length is 3.05 Å. The K(1)-O(4) bond length is 2.73 Å. The K(1)-O(7) bond length is 2.95 Å. There are two inequivalent V sites. In the first V site, V(1) is bonded to one O(1), one O(3), one O(6), one O(7), and one O(8) atom to form distorted VO5 trigonal bipyramids that share  a cornercorner with one P(2)CO3 tetrahedra and corners with two equivalent P(1)CO3 tetrahedra. The V(1)-O(1) bond length is 1.95 Å. The V(1)-O(3) bond length is 1.98 Å. The V(1)-O(6) bond length is 1.98 Å. The V(1)-O(7) bond length is 1.59 Å. The V(1)-O(8) bond length is 1.95 Å. In the second V site, V(2) is bonded in a rectangular see-saw-like geometry to one O(2), one O(4), one O(5), and one O(8) atom. The V(2)-O(2) bond length is 2.00 Å. The V(2)-O(4) bond length is 1.96 Å. The V(2)-O(5) bond length is 1.97 Å. The V(2)-O(8) bond length is 1.97 Å. There are three inequivalent C sites. In the first C site, C(1) is bonded in a distorted bent 120 degrees geometry to one C(3) and one P(1) atom. The C(1)-C(3) bond length is 1.52 Å. The C(1)-P(1) bond length is 1.80 Å. In the second C site, C(2) is bonded in a bent 120 degrees geometry to one C(3) and one P(2) atom. The C(2)-C(3) bond length is 1.53 Å. The C(2)-P(2) bond length is 1.79 Å. In the third C site, C(3) is bonded in a water-like geometry to one C(1) and one C(2) atom. There are two inequivalent P sites. In the first P site, P(1) is bonded to one C(1), one O(1), one O(4), and one O(6) atom to form PCO3 tetrahedra that share corners with two equivalent V(1)O5 trigonal bipyramids. The P(1)-O(1) bond length is 1.53 Å. The P(1)-O(4) bond length is 1.52 Å. The P(1)-O(6) bond length is 1.53 Å. In the second P site, P(2) is bonded to one C(2), one O(2), one O(3), and one O(5) atom to form PCO3 tetrahedra that share  a cornercorner with one V(1)O5 trigonal bipyramid. The P(2)-O(2) bond length is 1.53 Å. The P(2)-O(3) bond length is 1.53 Å. The P(2)-O(5) bond length is 1.53 Å. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 150 degrees geometry to one K(1), one V(1), and one P(1) atom. In the second O site, O(2) is bonded in a 2-coordinate geometry to one K(1), one V(2), and one P(2) atom. In the third O site, O(3) is bonded in a 2-coordinate geometry to one K(1), one V(1), and one P(2) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one K(1), one V(2), and one P(1) atom. In the fifth O site, O(5) is bonded in a bent 120 degrees geometry to one V(2) and one P(2) atom. In the sixth O site, O(6) is bonded in a distorted bent 150 degrees geometry to one V(1) and one P(1) atom. In the seventh O site, O(7) is bonded in a single-bond geometry to one K(1) and one V(1) atom. In the eighth O site, O(8) is bonded in a bent 150 degrees geometry to one V(1) and one V(2) atom. Linkers: 8 [O]P([O])(=O)[C][C][C]P([O])([O])=O. Metal clusters: 8 [K] ,16 [V]. The MOF has largest included sphere 4.30 A, density 1.78 g/cm3, surface area 2607.00 m2/g, accessible volume 0.17 cm3/g