Scientists have now discovered a new form of carbon, capable of withstanding extreme pressure levels previously only known for diamond
Carbon is the fourth element in its distribution in the universe and its forms are varied and different, including diamond, graphite and graphene. Scientists have now discovered a new form of carbon, capable of withstanding extreme pressure levels previously only known for diamond. This groundbreaking discovery was published in the scientific journal Physical Review Letters.
The research team from Stanford University, led by researcher Wendy L. Mao, began its experiments with a form of carbon known as glassy carbon, which was first synthesized in the 400s and was found to combine desirable properties of glass and ceramics along with those of graphite. The researchers created the innovative form of carbon by compressing glassy carbon at a pressure that is XNUMX times higher than atmospheric pressure.
This new form of carbon was able to withstand pressure 1.3 million times atmospheric pressure in one particular direction, while being limited to 600 times normal atmospheric pressure in the other directions. No material, with the exception of diamond, has been able to withstand such levels of pressure, a fact that indicates that the new form of carbon must indeed be extremely rigid.
However, unlike diamond and other crystalline forms of carbon, the structure of this new material is not organized into repeating atomic units. It is an amorphous material, that is - its structure lacks the long-term order of crystals. This amorphous and extremely hard form of carbon may have an important potential advantage compared to diamond if it turns out that its hardness is equal in strength in all directions (ie - an isotropic material). In contrast, the hardness of the diamond is closely dependent on the directionality of the crystal formation.
"These findings open a window to possible applications, including particularly strong anvils for research in high-pressure environments and could lead to the development of new families of extremely compressed and strong materials," explains one of the researchers.
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Pine,
It is not a matter of interpretation. Even if a short explanation is given, the explanation should be correct.
@Student, Technion
Look, from a theoretical point of view you are of course right in every word (knowledge of chemistry - an advantage). But there are two issues here:
1. I quoted the important sentence in the article that answered the question raised in a previous response. I should have given a brief explanation of some technical concepts otherwise it would have been pointless. How much I really want to go deeper into the explanations here is an open question. I am not interested in teaching a chemistry class 🙂
2. The bottom line of the article is that they took an amorphous material with almost 100% sp2 bonds, pressed it, then tested and found it turned into an amorphous material with almost 100% sp3 bonds, and became as hard as a diamond.
In the previous response I put a link to a version of the article. You can browse it. If you have a different interpretation of the results than mine, please write it. I would love to read.
Pine,
Some of what you wrote is inaccurate and some is incorrect.
A molecular orbital is a description belonging to the theory of molecular orbitals (MO Theory) and hybrid orbitals (sp, sp2...) are descriptions belonging to the hybridization theory (Hybridization theory). The more accurate theory is MO, in hybridizations still use crude or simplistic descriptions, when possible. Not true for relating bond strength to the hybrid orbital, it is not a necessary correlation. However, in abstraction, in bonds between carbons it is possible to do this. In this case, it is precisely carbons that are bonded to each other in sp2 hybridization orbitals that have a stronger bond - these are carbons that are bonded to each other in a double bond, compared to sp3 orbitals that describe carbons that are bonded in a single bond. Respectively, sp orbitals describe triple bonded carbons.
What happens in graphite is that the carbons are bonded to each other in a configuration of surfaces of benzene rings, where the hybrid orbitals are sp2. The weak connection you are talking about is between the layers of graphite (graphene) - the layers of the benzene rings - these are connected by pi-pi bonds by overlapping the total pi cloud of each layer.
The "strong" properties that a diamond has come from the spatial arrangement of the carbons in it (similar to Adamantane), and not necessarily from the strength of the bond between each individual carbon.
Point, Oren:
I have no idea what really happened, but I can assume that the very fact that they conducted the experiment at all indicates that they predicted its results.
It seems to me that in this case - an actual physical experiment - is much simpler to perform than a simulation of the behavior of so many atoms (and in any case - even if the simulation predicted the result - it would be impossible to accept it as correct without the experiment).
@Ariel:
The article has been accepted for publication but has not yet been finally published (what is called in press parlance), but I found a pdf copy at:
http://slac.stanford.edu/pubs/slacpubs/14500/slac-pub-14641.pdf
The key phrase you are looking for is: (quote)
Here we compressed glassy carbon at ambient temperature and completely converted its sp2 bonding to sp3 while preserving its amorphous structure
Where sp2 is the molecular orbital that appears for example in the relatively weak bonds of graphite and sp3 is the molecular orbital that appears in strong bonds like in diamond.
And in simpler words: by applying pressure, they were able to change the weak molecular bonds (like graphite) in the original material to strong ones like diamond, but the structure remained amorphous.
@point:
You are charmingly optimistic 😉
Ariel,
It is claimed that the material does not have a defined atomic structure - amorphous.
Too bad there is no link to the article. The news is not about the article but about the "research".
In the original news, how strange, it was claimed that the study would be published later.
Oh well.
But how come they didn't know about such material until now? Simulations did not show such a possibility?
Cool! By the way, I know and teach the concept of "form" as an "allotrope". Is the atomic structure of the new allotrope known and why is it so difficult?