K2Pt2P8O20I crystallizes in the tetragonal P4nc space group. K(1) is bonded in a 6-coordinate geometry to one O(1), one O(4), one O(5), one O(6), one O(7), and one O(9) atom. The K(1)-O(1) bond length is 2.88 Å. The K(1)-O(4) bond length is 2.83 Å. The K(1)-O(5) bond length is 3.00 Å. The K(1)-O(6) bond length is 2.98 Å. The K(1)-O(7) bond length is 2.86 Å. The K(1)-O(9) bond length is 2.88 Å. There are four inequivalent Pt sites. In the first Pt site, Pt(1) is bonded to one Pt(2), four equivalent P(1), and one I(1) atom to form distorted corner-sharing PtP4PtI octahedra. The corner-sharing octahedra are not tilted. The Pt(1)-Pt(2) bond length is 2.86 Å. All Pt(1)-P(1) bond lengths are 2.34 Å. The Pt(1)-I(1) bond length is 2.95 Å. In the second Pt site, Pt(2) is bonded to one Pt(1), four equivalent P(2), and one I(2) atom to form distorted corner-sharing PtP4PtI octahedra. The corner-sharing octahedra are not tilted. All Pt(2)-P(2) bond lengths are 2.32 Å. The Pt(2)-I(2) bond length is 3.13 Å. In the third Pt site, Pt(3) is bonded to one Pt(4), four equivalent P(3), and one I(2) atom to form distorted corner-sharing PtP4PtI octahedra. The corner-sharing octahedra are not tilted. The Pt(3)-Pt(4) bond length is 2.76 Å. All Pt(3)-P(3) bond lengths are 2.34 Å. The Pt(3)-I(2) bond length is 2.81 Å. In the fourth Pt site, Pt(4) is bonded to one Pt(3), four equivalent P(4), and one I(1) atom to form distorted corner-sharing PtP4PtI octahedra. The corner-sharing octahedra are not tilted. All Pt(4)-P(4) bond lengths are 2.35 Å. The Pt(4)-I(1) bond length is 2.76 Å. There are four inequivalent P sites. In the first P site, P(1) is bonded in a distorted trigonal non-coplanar geometry to one Pt(1), one O(1), one O(2), and one O(3) atom. The P(1)-O(1) bond length is 1.56 Å. The P(1)-O(2) bond length is 1.49 Å. The P(1)-O(3) bond length is 1.62 Å. In the second P site, P(2) is bonded in a distorted trigonal non-coplanar geometry to one Pt(2), one O(3), one O(4), and one O(5) atom. The P(2)-O(3) bond length is 1.62 Å. The P(2)-O(4) bond length is 1.51 Å. The P(2)-O(5) bond length is 1.60 Å. In the third P site, P(3) is bonded in a distorted trigonal non-coplanar geometry to one Pt(3), one O(6), one O(7), and one O(8) atom. The P(3)-O(6) bond length is 1.50 Å. The P(3)-O(7) bond length is 1.58 Å. The P(3)-O(8) bond length is 1.61 Å. In the fourth P site, P(4) is bonded in a distorted trigonal non-coplanar geometry to one Pt(4), one O(10), one O(8), and one O(9) atom. The P(4)-O(10) bond length is 1.51 Å. The P(4)-O(8) bond length is 1.61 Å. The P(4)-O(9) bond length is 1.57 Å. There are ten inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to one K(1) and one P(1) atom. In the second O site, O(2) is bonded in a single-bond geometry to one P(1) atom. In the third O site, O(3) is bonded in a distorted bent 120 degrees geometry to one P(1) and one P(2) atom. In the fourth O site, O(4) is bonded in a distorted single-bond geometry to one K(1) and one P(2) atom. In the fifth O site, O(5) is bonded in a distorted single-bond geometry to one K(1) and one P(2) atom. In the sixth O site, O(6) is bonded in a single-bond geometry to one K(1) and one P(3) atom. In the seventh O site, O(7) is bonded in a distorted single-bond geometry to one K(1) and one P(3) atom. In the eighth O site, O(8) is bonded in a bent 120 degrees geometry to one P(3) and one P(4) atom. In the ninth O site, O(9) is bonded in a distorted single-bond geometry to one K(1) and one P(4) atom. In the tenth O site, O(10) is bonded in a single-bond geometry to one P(4) atom. There are two inequivalent I sites. In the first I site, I(1) is bonded in a linear geometry to one Pt(1) and one Pt(4) atom. In the second I site, I(2) is bonded in a linear geometry to one Pt(2) and one Pt(3) atom. Linkers: 16 O=P(=O)OP(=O)=O. Metal clusters: 8 [O][P]O[K].[O][P][O].[O][P][O].[O][P][O]. The MOF has largest included sphere 5.04 A, density 2.47 g/cm3, surface area 1913.05 m2/g, accessible volume 0.14 cm3/g