Noticed this Slashdot thread, about a press release about synthesis of trinitramide, N(NO2)3. As noted by people in the thread, trinitramide is unlikely to be useful since it is unlikely to be easy to synthesize, handle and apply. That (and an earlier discussion tonight with my brother about what limits there should be in the chemistry education I will give to his kids) reminded me of a fun topic: horrible rocket fuels. Essentially any chemical with a lot of energy has been considered, and most have nasty properties in terms of explosiveness, toxicity and corrosiveness. Liquid rocket fuels are particularly horrific. One favourite is pentaborane, alias "green dragon". It can ignite spontaneously in contact with air, happily forms nasty shock sensitive compounds, reacts violently with water, is highly toxic (nerve agent level) and can even produce frostbite by evaporating from skin (while poisoning you). Chlorine trifluoride manages to be a more powerful oxidizer than oxygen itself, fluoridates *everything* and of course have other nasty properties. It will burn through sand. As John Clark is quoted in that post:

Quote:

”It is, of course, extremely toxic, but that's the least of the problem. It is hypergolic with every known fuel, and so rapidly hypergolic that no ignition delay has ever been measured. It is also hypergolic with such things as cloth, wood, and test engineers, not to mention asbestos, sand, and water-with which it reacts explosively. It can be kept in some of the ordinary structural metals-steel, copper, aluminium, etc.-because of the formation of a thin film of insoluble metal fluoride which protects the bulk of the metal, just as the invisible coat of oxide on aluminium keeps it from burning up in the atmosphere. If, however, this coat is melted or scrubbed off, and has no chance to reform, the operator is confronted with the problem of coping with a metal-fluorine fire. For dealing with this situation, I have always recommended a good pair of running shoes.”

Fluorine-oxygen mixtures have been used in the form of FLOX - a liquid fluorine/liquid oxygen mix. That is a seriously frightening idea. Remember that liquid oxygen has so high oxygen partial pressure that the oil in fingerprints will explode when the liquid pours past. Now mix that with nastiest-kid-on-the-halogen-block fluorine... Most current rockets use the far milder combinations of liquid oxygen (LOX) with kerosene or liquid hydrogen. Hydrazine, which is in use, is highly toxic and dangerously unstable. (several of these have been featured on http://pipeline.corante.com/archives/things_i_wont_work_with/ - a great read for anybody who likes spicy chemistry) This post is mostly to show space workers in Eclipse Phase how lovely their work environment actually is. Thanks to metallic hydrogen (which is just explosive), antimatter and small reactors they do not have to worry about the colourful hazards of bygone ages. Still, salvaging really old equipment or stuff built by eccentric designers ("If we can stabilize hydrogen, we ought to be able to stabilize nitrogen too!!!") will introduce some of the old horrors.