Sciencemadness Discussion Board

Nitro-fullerenes

BASF - 3-4-2003 at 11:08

While it seems impossible to nitrate carbon-fullerenes to an extent that they could be used as explosives, nitrogen-fullerenes may have a future:

http://www-cms.llnl.gov/s-t/ex_soccer.html

http://www.llnl.gov/str/June01/Manaa.html


[Edited on 3-4-2003 by BASF]

Cappy - 3-4-2003 at 12:34

It's funny. I was thinking about how N4 would have a low density from probably being gaseous at room temperature and pressure. Then I thought, buckminsterfullerene only has london dispersion forces, and it's a solid at room temperature. So I wondered if nitrogen fullerenes would be possible. Thanks for the links!

Blind Angel - 3-4-2003 at 13:36

does Phosphorous, Silicium, Germanium... fullrene can exist so?

BTW: i did the molecule over Chemsketch and it turned in a Lightbulb shaped fullrene, why is not "perfectly" round like C<sub>60</sub>? (or it's only chemsketch)

[Edited on 3-4-2003 by Blind Angel]

pitty

mykhal - 4-4-2003 at 06:50

What a pitty I did not read this few days before. Recently I have done some presentation - seminary work about fullerenes. (BTW: many scientific articles and reviews now lay on my disk - any interest?) These links are very interesting.

fullerenes

Krypton - 4-4-2003 at 07:52

I know the existing 6-nitro-fullerene, a very expensive energetic material, was not the only one what was synthesized.
The informations are low even when a energetic nitro compound.
I think a interested theme is the usage of sphere components as a energetic material.

pardon?

mykhal - 4-4-2003 at 08:04

Quote:
Originally posted by Krypton
I know the existing 6-nitro-fullerene, a very expensive energetic material, ....


I'm not sure what do you mean by <i>6-nitro-fullerene</i>.

hexaazabuckminsterfullerene C<sub>54</sub>N<sub>6</sub> ?
or nitrobuckminsterfullerene C<sub>60</sub>NO<sub>2</sub> ?
or hexanitrobuckminsterfullerene C<sub>60</sub>(NO<sub>2</sub>;)<sub>6</sub> ?

Krypton - 4-4-2003 at 08:11

I mean 6-nitrofullerene.

C60NO2

and not hexanitrofullerene.
Have you any sources or articles of the other compounds ?

mykhal - 4-4-2003 at 08:30

Quote:
Krypton: I mean 6-nitrofullerene.

Oh, I was confused by that `6'. There would be only one nitrofullerene (provided that you mean C<sub>60</sub> by `fullerene';), because all C-atoms are equivalent. But I cannot imagine mononitrofullerene. There would be one dangling electron present. I can imagine e.g. C<sub>60</sub>(H)(NO<sub>2</sub>;) or C<sub>60</sub>(NO<sub>2</sub>;)<sub>2</sub>. As far as I know, hexanitrofullerene exists.

PHILOU Zrealone - 7-4-2003 at 03:47

Fullerenes:
N-20
N-60
Aromatic:
N-6

Have equivalent N and many symetry axis!
That play strong role in stability!
As soon a dissymetry occurs bond lenght may become unequal and explosive decomposition occure!

mykhal - 9-4-2003 at 10:34

Quote:
Originally posted by PHILOU Zrealone
Fullerenes:
N-20
N-60
Aromatic:
N-6

Have equivalent N and many symetry axis!
That play strong role in stability!
As soon a dissymetry occurs bond lenght may become unequal and explosive decomposition occure!


Could you please explain more clearly what did you mean by N-<i>x</i> ?

Madog - 9-4-2003 at 11:19

he means the amount of Ns in them.

mykhal - 9-4-2003 at 12:01

Quote:
Originally posted by PHILOU Zrealone
Fullerenes:
N-20
N-60
Aromatic:
N-6

Have equivalent N and many symetry axis!
That play strong role in stability!
As soon a dissymetry occurs bond lenght may become unequal and explosive decomposition occure!


It is funny, because you cannot say if some fullerene or it's derivative is aromatic. These compounds have more or less aromatic character. As far as i know, polyazafullerenes have not been isolated. There are only some theoretical calculations on them.

PHILOU Zrealone - 10-4-2003 at 06:08

Stronger than stronger; they should theoricise:
N6 aromatic ring entrapped inside N20 fullerene itself trapped inside N60 fullerene!

This would make a nice matriochka structure!
N(N(N6)20)60 thus inside a N60 volume the equivalent of N-86!


:D:D:D:cool::cool::cool::o:o:o:P:P:P:):):);););)

mykhal - 10-4-2003 at 08:14

Wow, you mean nitrogen onions - analogous to carbon bucky onions. But have on mind that everything you create in your favorite molecular modelling program deos not necessarily have to exist.
Matriochka structures and endohedral fullerene derivatives are commonly noted following way - in case of your hypothetical (but who knows? :) "compound" : N<sub>6</sub>@N<sub>20</sub>@N<sub>60</sub>

PHILOU Zrealone - 10-4-2003 at 10:18

Yep for now theoricising!
50 years ago hexanitrobenzene was view of the mind; but a few decades ago it has been done!
It was only 8 years ago; synthesis of octanitrocubane was tought to be impossible! Now it is done!
N5 compounds follows the same pathway!
....
So as soon as N6, N20, N60 have been done (in a century or more ;) less I hope) I have already the idea to put them in each other!

Just theorically, I wonder what is the properties of N6@N20@N60 vs N6, N20 and/or N60?
:cool:

poly nitro fullerenes

jrdobbs - 1-12-2004 at 13:26

Earlier it was stated "it seems impossible to nitrate carbon-fullerenes to an extent that they could be used as explosives". Why should that be?

[Edited on 1-12-2004 by jrdobbs]

JohnWW - 1-12-2004 at 19:36

It would be impossible to obtain an N60 isoelectronic with C60, with each N pentavalent and bonded to 3 others by 4 resonating covalent bonds, because it would be a quaternary ammonium cation bearing 60 positive charges, one on each N, for that to happen, N60(60+). The internal repulsion would be too great. But you may be able to get a N60 formed entirely of trivalent nitrogen, each N bonded to 3 others by 3 covalent bonds with a lone pair of electrons on each N, isoelectronic with completely hydrogenated C60. Subjecting solid N2 to extreme pressure might do it, but you would be at least as equally likely to get an infinite planar hexagonal lattice of Ns, or an electrically-conducting linear polymer, (-N=N-N=N-N=N-)n.

Other possible related compounds would include borazofullerene, B30N30, with alternating B and N atoms, isoelectronic with C60, and positive charges on the pentavalent Ns and negative charges on the trivalent Bs. It would be similar to the graphite form of BN (which also has a diamond form as hard as real diamond).

Also, at least one carbon in C60 could be replaced with N+ to form a singly charged quaternary ammonium cation, C59N+. Assuming that it is possible to replace the maximum number of Cs with N+s such that no N+ is bonded to another N+, substitution up to C45N15(15+) should be possible.

neutrino - 2-12-2004 at 03:25

That’s what the articles mostly talked about. I'm thinking that this thread should be renamed to ‘azo-fullerenes” to avoid further confusion.

I don’t think your N-N=N-N=N chair would be very stable. Judging by the atomic shape, this would be like one big peroxide molecule waiting to go off.

IIRC, hexagonal BN is soft like graphite. Cubic BN is the one with diamond-like hardness (in fact, it is second only to diamond).

Marvin - 2-12-2004 at 14:33

There is a better thread on why complex nitrogen structures akin to N60 don't occur.

BN is indeed isoelectronic with C2 and some resemblence occurs. Aromaticity is neerly non existant though with borazine simply adding to HCl for example. Rings in fullerenes are virtually non aromatic anyway and the reason has been given that its due to the system not being planar. Halogens tend to hydrolyse from the surface on contact with water for example. Before the bubble burst on all the initial ideas for fullerenes in the early 90's I asked about the possability of borazine type fullerenes and the reply gave me a classic "DOH!" moment. The required alternating B N B N system cant exist throughout because fullerenes have (and unavoidably require) pentagons.