The structure of the title compound, C8H16N4, which consists of four fused seven-membered rings, has been redetermined at 173 K. This redetermination corrects the orientation of two H atoms, which were located at unrealistic positions in the original room-temperature study [Murray-Rust (1974 ▶). J. Chem. Soc. Perkin Trans. 2, pp. 1136-1141]. The complete mol-ecule is generated by -42m symmetry, with one quarter of a mol-ecule [one N atom (site symmetry m), two C atoms (one with site symmetry m and the other with site symmetry 2) and two H atoms] in the asymmetric unit. No directional inter-actions beyond van der Waals contacts are apparent in the crystal structure.
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