Azidotetrazolate (CN7−) is an anion which forms a highly explosive series of salts.
The nitrogen base compounds have the advantage of being "green explosives", meaning that their waste products are safe.
Guanidinium azidotetrazolate could be melted to an ionic liquid at 100°C, but would decompose smoothly at 159°.
The NNN side chain is attached to the carbon atom, and bent at the first nitrogen so that it is roughly parallel to the ring.
The 2H version with hydrogen attached in the second nitrogen from the carbon is purportedly more stable in the gas phase.