The Ghost In The Machine (or somebody else of the same name) wrote thusly in
message :

I also seem to recall -- don't remember the details now -- of a
theoretical explosive that basically fizzled. Something tells me
we have a long way to go before predictive chemistry becomes the
norm. :-)

Octanitrocubane C8(NO2)8 is predicted to be a more powerful explosive than
most of what the military are using now, and safer to handle.

Predicted. Up till now nobody has got more than two nitro's onto the cubane
nucleus.

If "polyyne" is really -C≡C-C≡C- (that's alternate single and triple bonds
between the carbons in case the character doesn't come out) I can't see how
it can be stable - the triple bond is not "the strongest" bond but the most
reactive. Also the linear structure would be strong in one dimension only
giving the stuff a fibrous texture.
--
Warning: keel away from child for hot bulb

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