A hex upon you!

This is hexazine. And it probably doesn’t really exist. Denoted N6, if it does exist it would be an unstable allotrope* of nitrogen. It’s an analog of benzene, and just like benzene it would be aromatic. If it existed. Computational chemistry predicts it to be highly unstable. Perhaps it might form at extremely low temperatures for very short lengths of time… but I wouldn’t bet money on it. This molecular oddball is more of a chemical curiosity than anything else.

A curious thing about chemistry is that some elements act very similarly to each other. Similarly, but not exactly the same. Take carbon and nitrogen, for instance. Carbon likes to make hexagons**. Graphite is essentially a molecular sheet of chickenwire, composed of nothing but fused hexagons. Take just one hexagon, and cap each carbon atom with a hydrogen, and you have benzene. Nitrogen, on the other hand, isn’t massively fond of hexagons, but all the same, as long as you have enough carbon around to show it what to do, it’ll play nice. Swap one carbon atom with a nitrogen, and you have pyridine. Nitrogen, conveniently enough, doesn’t need to be capped with hydrogen. You can you can swap atoms this way up to 4 times, creating tetrazine… but no more than 4 times. Nitrogen also likes to pair up, so if you put too much of it in the same place, it’ll try to revert to N2, which is a much more stable molecule (there’s a reason why Earth’s atmosphere is mostly N2).

Molecules like hexazine are only really of interest to theorists, though they occasionally have real world applications if they can be synthesised. Nitrogen compounds, however, tend to be relegated to use as rocket fuels and explosives. Following the footsteps of molecules like hydrazine, nitrogen compounds tend to be unstable, and will combust violently if you give them a chance to. Octaazacubane is another such hypothetical explosive nitrogen molecule. Others, like pentazole, have actually been created. And yes, they’re explosive too. Nitrogen is rather bipolar that way. Either it’s extremely stable, or remarkably unstable. Maybe it would be better not to mess with it…

*Allotropes are different molecular structures of the same element. Carbon, for instance, can exist as diamond, graphite and fullerene, amongst other structures.

**I’ve remarked in the past that I’ll soon have a PhD in drawing hexagons!

About Invader Xan

Molecular astrophysicist, usually found writing frenziedly, staring at the sky, or drinking mojitos.
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One Response to A hex upon you!

  1. Eduardo Monteiro da Costa says:

    What about N4, it has an square shape and two bonds cross passing each other

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