Hexazine

Hexazine is a predicted chemical compound with the formula N6.

Hexazine would have molecules of six Nitrogen atoms, arranged in a ring structure (analogous to benzeneplugin-autotooltip__plain plugin-autotooltip_bigBenzene structure

The benzene molecule is composed of 6 carbon atoms joined in a ring with 1 hydrogen atom attached to each. Because it contains only carbon and hydrogen atoms, benzene is classed as a hydrocarbon.

Although the compound has been very extensively studied since its first isolation in 1825, its molecular dynamics - especially at temperatures below 77K when it becomes a solid - are extremely complex and the underlying atomic mechanics are for the most part still obscure.
).

Although molecular-force calculations appear to show that it's a viable compound, it has never been observed, and its properties are therefore unknown. Some computational analyses suggest that, unlike benzene, it would be highly unstable (ref.).