Endohedral clusterization of ten water molecules into a 'molecular ice' within the hydrophobic pocket of a self-assembled cage

An adamantanoid (H2O)(sub 10) cluster is formed, within the hydrophobic cavity of a self-assembled coordination cage, which is termed 'molecular ice' as this structure is the smallest unit of naturally occurring Ic-type ice. The x-ray structural analysis, coupled with neutron diffraction study, reveals that the molecular ice is not simply formed by filling the void space but is a result of specific H2O:...pi interaction within the cage.