Mo7O246

Mo7O246, commonly written as [Mo7O24]6−, is a heptamolybdate polyoxometalate anion. It is a discrete cluster containing seven molybdenum centers linked by oxide ligands, resulting in a highly charged anion with six negative charges. In solution, the [Mo7O24]6− anion typically forms under alkaline conditions and can pair with a variety of cations to give different salts.

Structure and properties are characteristic of polyoxometalates. The seven Mo centers are connected through Mo–O bonds in a compact oxide framework, enabling accessible Mo(VI)/Mo(V) redox transitions. This redox flexibility, together with strong oxide–oxide connectivity, contributes to chemical stability in basic media and to diverse reactivity in inorganic synthesis and catalysis. The anion is usually handled as a salt, with common forms including alkali metal and ammonium salts, and can be crystallized or isolated in solution as needed for study or application.

Synthesis and handling generally involve dissolving molybdate sources in basic water to generate the [Mo7O24]6− species. Salt formation with various countercations yields a range of solid and aqueous reagents. The compound is typically stable under neutral to basic conditions but can undergo changes upon reduction or exposure to strongly acidic environments.

Applications of heptamolybdate species include serving as a building block for molybdenum oxide materials, a catalyst precursor for oxidation reactions, and a component in electrochemical and supramolecular systems. As a representative polyoxometalate, it is also used in studies of electron-transfer processes and in the design of new inorganic materials.

See also: Polyoxometalates, Molybdate, Heptamolybdate.