Synthesis and structure of pentakis(2-aminopyridinium) nonavanado(V)tellurate(VI)

In the title compound, (C5H7N2)(5)[TeV9O28], the tellurium and vanadium atoms are statistically disordered over two of the ten metal-atom sites in the [TeV9O28](5-) heteropolyanion. The anions stack along [100] and are extended into a three-dimensional supramolecular network through N-H center dot center dot center dot O and weak C-H center dot center dot center dot O hydrogen bonds involving the self-assembled 2-aminopyridinium pentamers, which are linked by C-H center dot center dot center dot pi and pi-pi stacking interactions. The most important contributions to the Hirshfeld surface arise from O center dot center dot center dot H/H center dot center dot center dot O (54.8%), H center dot center dot center dot H (17.8%) and C center dot center dot center dot H/H center dot center dot center dot C (13.4%) contacts.