New Form of Carbon is Stronger Than Graphene and Diamond | Hacker News Reader

New Form of Carbon is Stronger Than Graphene and Diamond

technologyreview.com

87 pointsqubitsam50 comments

"They agree that two chains in contact can react but there is an activation barrier that prevents this happening readily." So, it's really strong but if it ever actually breaks it will explode?

So it's slightly similar to Prince Rupert's Drops, where part of the drop is extremely strong but if the weaker part is broken the whole thing explodes.

http://en.wikipedia.org/wiki/Prince_Rupert's_Drop

The mutual frustration imposed in PRDs is due to how it cools and the mechanics of a bulk state (tension on the surface and positive pressure in the core).

What they're talking about in this paper is a chemically reactive state which is avoided due to an energy barrier. They're totally different situations, but I can understand why you'd think they might be similar from the wording of the article.

> a chemically reactive state which is avoided do to an energy barrier.

So sort of like how gunpowder is stable unless you introduce enough energy to get it over the hump?

Yes.

Basically it's flammable with an ignition temperature right around room temperature. If we can keep it cold it might have some uses.

I completely understand the difference so I almost didn't post the link, but I think PRDs are awesome and I couldn't resist a minuscule opportunity to post about them.

Thanks for explaining the difference for anyone who may have been misinformed by my post.

Thanks. There's some pretty cool stuff on youtube about this. (I'd never heard of it before)

If I recall, the same is true of Gorilla Glass.

I don't mean figuratively exploding as in shattering quickly into a large number of tiny fragments. I mean that I'm worried that it will literally explode, detonating or deflagrating, transforming into a different chemical substance and releasing a large amount of energy along the way.

It sounds to me like a slow degradation, not anything that would runaway.

I'm sure that it does degrade like that at normal temperatures. Normal explosives will also tend to degrade slowly over time as the chemical reactions that power their explosion also have a "activation barrier that prevents this happening readily". But as the temperature increases probability that any given molecular interaction will exceed that activation barrier increases. And if the activation barrier is exceeded, a chemical reaction happens that will release energy and increase the local temperature. In some substances if you increase the local temperature by enough there will be a runaway reaction which will quickly liberate all of the available chemical energy, an explosion. This all has to be triggered, but the strength of the substance makes me think that the energy involved in breaking it ought to be enough.

Now, it might be that the energy required to get over the potential barrier is large enough compared to the energy released by the reaction that this doesn't happen. If there people with real chemistry experience here instead of just semiconductor physics and basic statistical mechanics I'd be grateful if they'd speak up. I'm mostly inferring from the prior beliefs of other chemists that this substance wouldn't be stable at all that it will tend to explode if given a chance.

I spoke with a professor ( http://en.wikipedia.org/wiki/Walt_de_Heer ) once about a question somewhat related to this topic, specifically in cluster physics, regarding the formation of stable condensates of atomic clusters. An atomic cluster is sort of a jelly ball of atoms, where the orbitals, rather than being organized into nice molecular bonds, have become nonlocal and the whole thing acts as a sort of "superatom". They can carry a charge, as in the Zintl clusters e.g. Pb_9(4-): nine lead atoms with four extra electrons. In some very rare cases the clusters form metastable compounds.

When I asked de Heer's opinion on producing condensates of clusters, he said quickly "it's a bomb!". Apparently there is so much energy in these unfavorable molecular configurations that you would never want to try to isolate a substantial amount of them. I imagine a similar principle applies to carbyne.

Carbyne and other myths about carbon

http://www.rsc.org/chemistryworld/Issues/2010/November/Carby...

That article is from years ago, and this current article is based on a paper published a few weeks ago. Science advances.

Actually not so much. Reading the article it talks about the difference between trying to infer the possibility from the reality, and the OP is a theoretical result. Basically this stuff has never been seen "for real" as far as we (and scholar.google.com) seem to know.

I did learn something new though, which is the exothermic properties of carbyne re-assembling itself into more stable configurations is pretty amazing. If nothing else, if you could make carbyne and stabilize it, and then destabilize it on demand, it would make for a heck of an explosive and one with presumably no nitrogen atoms. The implications of that are pretty obvious.

The implication is that we design a carbyne detector and get filthy rich selling it to the Department of Fatherland Carbyne.

Heh, I like that idea. Since its highly improbable anyone will make one anytime soon, we can sell them a detector with meters and lights and screens maybe for millions of dollars, which can't detect anything but will have a perfect success record!

Apparently all of the carbyne related domains where available and then registered by someone soon after this was posted.

Squatters confuse and irritate me.

"New Form of Carbon is Stronger Than Graphene and Diamond" "Chemists have calculated ... carbyne, should be stronger and stiffer than any known material"

So which is it, 'it is stronger' or 'it should be stronger'?

> So which is it, 'it is stronger' or 'it should be stronger'?

That language simply acknowledges that to date, the work is mostly theoretical -- they don't have enough material to perform empirical measurements. Another way to say it is that it's theoretically stronger, and it will probably be stronger in reality as well.

The study is entirely based on first principles simulations. So even though these may be the most accurate calculations we can possibly carry out... they still may not be experimentally validated (for any number of reasons). In this case they cannot state anything as 100% truth as it has not (necessarily) been tested through experiment. "should" is appropriate.

I expect better writing from MIT Technology Review than to say something as vague as "stronger than diamond". I assume that they mean tensile strength, but it's important to actually say that.

Just as impressive is the new material’s strength. Liu and co calculate that it takes around 10 nanoNewtons to break a single strand of carbyne. “This force translates into a specific strength of 6.0–7.5×10^7 N∙m/kg, again significantly outperforming every known material including graphene (4.7–5.5×10^7 N∙m/ kg), carbon nanotubes (4.3–5.0×10^7 N∙m/ kg), and diamond (2.5–6.5×10”7 N∙m/kg4),” they say.

Deleted comment

No, think of it as 4.5e8 compared to 1e9.

No they are correct.

Since two chains of carbine coming in contact would explode, should the activation barrier be crossed, does this mean we can only use one chain at a time...i.e. no stringing together multiple chains to make something like say...the cable for a space elevator?

Unless we can keep it cold. An "activation barrier" is just another way of saying you need to heat it to make it burn.

Or in other words: It's flammable, and the ignition temperature is right around room temperature.

So we might need some sort of active cooling mechanism, considering how a space elevator cable, afaik, has to be anchored near the equator, which is typically hotter than room temperature? What if the cooling fails? I don't know much about QM or the chemistry of carbynes, but is it possible for some electrons to spontaneously jump over the activation barrier (despite being cooled) and start off some chain reaction that could jeopardize the entire space elevator cable?

> but is it possible for some electrons to spontaneously jump over the activation barrier (despite being cooled) and start off some chain reaction

Probably not, because if they could then ordinary things would spontaneously catch fire too. (Maybe they do??)

Wish nanotechnology would progress faster I'm really excited about the potential applications of these new materials.

The only real application at the moment is securing additional grant funding.

Carbyne? Good grief. What is coming next? Carbone, Carbonne, Carboon, Carborola?

OK, joking aside. I am still waiting for Graphene to become used in any commercial application at all. For all its hype, nothing has been seen yet. Is it not yet economical to produce?

When might Carbyne become used commercially, and what are the steps needed between now and that time?

Carbyne is a quite logical name, considering the -y- vowel (and even the -yne ending) is used to denote triple bonding between carbon atoms in organic chemistry.

Compare ethane - ethyne (single bond - triple bond), for example.

Molecules are given names after very specific rules, which allow you to identify the structure from the name alone. Those are not just made up by bored chemists.

So, no Corbomite next?

http://en.wikipedia.org/wiki/The_Corbomite_Maneuver

Carbonara :-)

Actually, I think 'Dimondium' is next, followed by 'Dimondillium'.

Maybe 'Carbyne' was a spelling mistake, like the numerous others in that article!

It's your regular Org Chem nomenclature.

I'm still waiting for cheap sheets of graphene.

What are you going to do once you get that cheap sheet of graphene?

Get rid of indium tin oxide in my touchscreens and use graphene as the base conductor.

Ideally build a space elevator.

find something that can cut it.

A better quadcopter.

Make a really conductive frisbee.

I'd build stuff from them. Surf boards, bulletproof shirts and pants, whatever.

Let's wait and see if it is the next chrysotile asbestos.

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