Mechanistic insights into template-driven polyoxovanadate self-assembly: the role of internal and external templates.

The self-assembly of molecular metal oxides, polyoxometalates (POMs), can be controlled using internal or, more rarely, external templates. Here, we explore how the interplay between internal templates (halides, oxoanions) and organic external templates (protonated cyclene species) affect the self-assembly of a model polyoxovanadate cluster, [VOX] (X = Cl, Br, NO). A combination of crystallographic analyses, spectroscopic studies and as well as solid-state V NMR spectroscopy provide critical insights into the initial formation of an intermediate vanadate species formed during the process.