Structure of a Three-Dimensional, Microporous Molybdenum Phosphate with Large Cavities

Abstract
The synthesis, single-crystal x-ray structural characterization, and sorption properties of a microporous molybdenum phosphate, (Me4N)1.3(H3O)0.7[Mo4O8(PO4)2] · 2H2O (Me, methyl), are presented. The three-dimensional framework is built up from Mo4O84+ cubes and PO43- tetrahedra that are connected in such a way that large, cation-filled voids are generated; these voids constitute 25% of the volume of the solid. Absorption isotherms for water show the completely reversible uptake of 4 to 5 percent by weight water into the micropores of this compound, which corresponds to 10 to 12 percent by volume.