Niobium(V) oxynitrate is an inorganic compound with the proposed formula NbO(NO3)3.
A single publication claims that niobium pentachloride and dinitrogen pentoxide react in anhydrous nitric acid at 30 °C to give niobium(V) oxynitrate and a nitryl chloride byproduct:
The synthesis is quite solvent-dependent. The same reagents in acetonitrile instead form a (acetonitrile)niobium(V) dioxynitrate complex.
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