Unveiling the Key Templates in the Self-Assembly of Gigantic Molybdenum Blue Wheels

Template synthesis is a powerful and useful approach to build a variety of functional materials and complicated supramolecular systems. Systematic study on how templates structurally evolve from basic building blocks and then affect the templated self-assembly is critical to understand the underlying mechanism and gain more guidance for designed assembly but remains challenging. Here we describe the templated self-assembly of a series of gigantic Mo Blue (MB) clusters 1-4 using L-ornithine as structure-directing agent. L-ornithine is essential for the formation of such kind of template⊂host assemblies by providing directional forces of hydrogen bonding and electrostatic interactions. Based on the structural relationship between encapsulated templates of {Mo8} (1), {Mo17} (2) and {Mo36} (4), a plausible pathway of the structural evolution of templates is proposed, thus giving more insight on the templated self-assembly of Mo Blue clusters.