A potassium selective 'nanosponge' with well defined pores.

The novel spherical cluster-compound K2Na6[K20 [symbol: see text] Mo80-V22O282(SO4)12(H2O)66]. approximately 140H2O 1 has been obtained in a 'one-pot' reaction and exhibits several remarkable structural features: 30 open shell centers, i.e. 8 Mov and 22 VIV spanning an icosidodecahedron, the incorporation of 20 K+ cations capping 20 appropriate [M6O6] pores/rings present at the surface of the spherical cluster-anion, and an encapsulated aggregate of water molecules.