NEW IMPETUS FOR INORGANIC HOST-GUEST CHEMISTRY

Already in 1826 Berzelius described (NH4)3[(PO4)Mo12O36]. Its anion consists of a shell of twelve MoO6 octahedrons surrounding a P atom, but can also be described as a central phosphate ion whose O atoms form part of the shell. Related to this ancient chemistry are more recent findings in inorganic supramolecular chemistry, which include results as diverse as the characterization of Cd(CN)2 . neopentane, in which the host Cd(CN)2 forms a network structure trapping neopentane within its cavities in an ordered fashion, and the binding of a NH4Cl dimer in a giant anionic cage, described by A. Muller et al. in this issue (see p. 1192).