Drawing Small Cations into Highly Charged Porous Nanocontainers Reveals “Water” Assembly and Related Interaction Problems

Containing nanowater droplets: A series of polyoxometalate capsules containing shells of water molecules is described. The surfaces of the capsules are covered with nanoscale pores, which when open permit entry to the cavities within (see structure, four of the 20 nanoscale pores are visible, and one of the six encapsulated Na+ ions is shown in violet). Variation of the cluster properties, such as charge and the nature of the internal surface, greatly influences the encapsulated species.