Giant Ring-Shaped Building Blocks Linked to Form a Layered Cluster Network with Nanosized Channels: [Mo_(124)~(VI)Mo_(28)~VO_(429)(#mu#_3-O)_(28)H_(14)(H_2O)_(66.5)]~(16-)

摘要

The synthesis of multifunctional inorganic materials from robust building blocks (synthons) that have a well-defined structure and can be linked together represents a constant challenge in crystal engineering. we report the synthesis of the deep blue mixed-valence (Mo~(VI)/Mo~V) compound Na~(16)[Mo_(124)~(VI)Mo_(28)~VO_(429)(#mu#_3-O)_(28)H_(14)(H_2O)_(66.5)] centre dot ca. 300 H_2O (1), which consists of nanosized wheel-shaped building blocks with 152 Mo atoms. These discrete building blocks can be prepared easily by reduction of an acidified aqueous molybdate solution and, when linked together, they form a layered open framework with nanosized channels. The encapsulated water molecules can be partly replaced by organic molecules. The metal-oxide-based host lattice has altogether 28 4d electrons per ring. These can be assigned to 14 incomplete double-cubane-type compartments spanned by five Mo and six O atoms, which show negligible electronic interaction. The two electrons delocalized in each of these compartments give rise to the deep blue colour.