Maker - 1-11-2015 at 12:41
I hope this isn't a stupid question, I'm only asking out of curiosity.
I was reading the wiki article about Octanitrocubane and it said it has the structure of cubane with each hydrogen atom replaced with a nitro group.
That got me thinking, could each hydrogen atom on a molecule of doedecahedrane be replaced with a nitro group?
PS; I feel rude not introducing myself, my name is Adam, I'm currently doing AS levels in chemistry, physics and maths. I don't have a lab yet but our
garage is my welding and machining workshop so I have a good space for a small lab 
[Edited on 1-11-2015 by Maker]
[Edited on 1-11-2015 by Maker]
PHILOU Zrealone - 1-11-2015 at 13:27
Theorically yes!
Practically not yet done! 
j_sum1 - 1-11-2015 at 14:35
I suspect that a highly nitrated buckyball will come first.
Maker - 1-11-2015 at 15:23
I didn't think a buckyball could be nitrated (Or bond with any functional group for that matter), because the valence electrons of each constituent
carbon atom are either bonded to more carbon atoms or delocalized, is this not true then?
[Edited on 1-11-2015 by Maker]
j_sum1 - 1-11-2015 at 16:25
Ok. You may well be right.
I was thinking primarily of starting substrate. I know of cubane and buckyballs. I have not heard of dodecane.
I will defer to the knowledge of the various organic chemistry gods on this site on the matter of nitration of buckyballs.
I do note that nitration of a benzene ring is indeed common (trinitrotoluene anyone?). By your rationalisation that would not be possible.
Really though, I am merely flipping ideas around in a pool that is way over my depth.
Tsjerk - 2-11-2015 at 05:40
Dodecahedrane and benzene differ from a buckyball in the sense its carbons still have a single hydrogen, which can be replaced. The wiki says
something about highly fluorinated/chlorinated dodecahedrane, by mixing with the corresponding halogen under high pressure, temperature and uv-light.
So I could imaging how one would convert the chlorinated species to a nitro-variant with the use of e.g. silver nitrate if a suitable solvent system
could be found.
Edit: all very hypothetical as the chlorinated version apparently could only be obtained in minute amounts. But maybe some microscale chemist could at
least show a partly nitrated version of the molecule.
[Edited on 2-11-2015 by Tsjerk]
Praxichys - 2-11-2015 at 08:47
Dodecanitro-dodecahedrane would probably be lower-performing than heptanitrocubane. First, the cubane structure stresses the C-C bonds considerably.
Dodecahedrane has nearly ideal bond spacing for minimum stress, and thus less energy released when rearranged. Second, heptanitrocubane has been found
to be more dense than oxtanitrocubane because changes in polarity across a molecule allow for better stacking. The dodecanitro-dodecahedrane would
probably not be very dense in comparison. Highly dense for an organic compound for sure, but not nearly as dense as HNC.
That, and as Tsjerk mentions, it is extraordinarily unreactive and would be very difficult to nitrate, just like ONC/HNC.
Tsjerk - 2-11-2015 at 11:35
Although this molecule would look very cool indeed! Imaging a 20 ball with just nitro's on the outside!
Praxichys - 2-11-2015 at 12:37
Try putting them on the inside. Now THAT would be really impressive! Almost like a little molecular bomb.
I wonder if something like this could be assembled with an aluminum atom in the center to improve heat output and density? It would be like a
clathrate, almost like an explosive zeolite with something adsorbed to increase output.
Tsjerk - 2-11-2015 at 12:58
OK, you got me there, I didn't imaging that one yet... Helium was put inside by shooting a sheet of it with atoms, so why not aluminium! OK, maybe too
big.
Maker - 2-11-2015 at 13:44
When you say an aluminium atom in the centre, I assume this means it's just "trapped" inside, not actually bonded?
On a slight tangent, could an atom such at ruthenium, osmium or iridium (+8 oxidation state?) be inside a molecule of cubane, bonded to each carbon
atom?
Pasrules - 2-11-2015 at 14:34
Bucky balls really just arnt reactive as stated earlier no hydrogen to replace, also any attacks can only be done on the outside of the molecule.
Chlorine works only because of it's UV radical. I don't know how far peroxide radicals would go.
I haven't heard of the helium being shot into a sheet which sounds interesting, I'm sure aluminium would work and could possibly activate the ball
taking it's mass into account and lower velocity. It might also be worth remembering that nitro groups are deactivating to benzene rings but I don't
know their effect in this situation.
To get nitro group on the inside is quite futile, if you put the groups onto a sheet it would never fold unless they became a network lattice with
each other which probably wouldn't be reactive.
Maybe firing aluminium nitrate at a sheet then putting a current through the ball but guns don't work like that. I'm stumped
Tsjerk - 4-11-2015 at 00:42
I didn't read it but they refer to a paper where they did it.
http://physicswikis.com/helium_atom/Helium_atom_trapped_in_f...
PHILOU Zrealone - 7-11-2015 at 04:54
The cavity Inside dodecahedrane is limited to less than two C-C bond lenght in diameter (about 2,5 C-C lenght minus 1 C radius in sp3 form).
Thus roughly cavity diameter = 154*2.5 - 76 = 232 pm (picometer)
So entraping single atom of tiny multiatomic molecules will be hard and limited in the number of possibilites.
Such a spherical molecule may prove to be more or equally performant than 7-NC and ONC (8-NC).
The main troubles comes for such molecules:
-from the cavity inside that may reduce a bit the density (inside void) this will be worst with larger fullerenes)
-from the molecular packing; one may think cubic will arrange perfectly to avoid all voids but 7-NC and 8-NC are not perfect cubes due to the
nitro-groups outside and so packing may not be optimal; also with spheroids packing one soon realises that there are outside voids and this effect
becomes worst with larger spheres.
Those effects can be counterballanced by playing with mixes of various radius spheres (tiny and very larger ones) or by entraping tiny molecules
inside the larger ones.
Best way to find out for 20-N-dodecahedrane is to make a computer simulation vs 7-NC and 8-NC in a box.
Here are some data and infos for the work:
Cubane: C8H8
T°f = 130-131°C
d = 1,29 g/cm³
Octanitrocubane: C8(NO2)8
d = 1,98 g/cm³
Dodecane: C20H20
T°f = 430°C
d = 1,434 g/cm³
--> Already denser than cubane what may be a good point for a denser than ONC (8-NC) 20-ND (dodecanitrododecane - pernitrododecane)
Now just for the fun of it some other interesting infos 
...
Pagodane: C20H20
d = 1,629 g/cm³
--> Already denser than many HE, denser than cubane and than dodecane... thus good start for a denser than ONC (8-NC) 20-PD (dodecanitropagodane -
pernitropagodane)
Prismane: C6H6
Already explosive hydrocarbon 
If dodecane or pagodane upon pernitration do both follow the same density increase rule as cubane to ONC... then roughly one may estimate the density
to become:
--> 2.20 g/cm³ for 20-ND 
--> 2.50 g/cm³ for 20-NP
This need more precise calculations of course!
[Edited on 7-11-2015 by PHILOU Zrealone]
franklyn - 10-11-2015 at 06:10
Using strained carbon molecules for fuel in a Sprengel admixture with the thought of forming a lattice work
somewhat as clathrates or such can give better total energy output. Reactivity is another matter.
Related formulation.
www.sciencemadness.org/talk/viewthread.php?tid=1970&page...