The structure determination of the title compound, C8H9N3O3, establish
es the N-oxide form of triazene. The overall molecular planarity and t
rigonal planar geometry of the triazene N atom bonded to the phenyl ri
ng suggest a resonance interaction extending over adjacent atoms. The
molecular conformation is stabilized by intramolecular hydrogen bonds
and the crystal packing by intermolecular hydrogen bonds.