Scientists create matter that can dent diamonds | Hacker News Reader

Scientists create matter that can dent diamonds

phys.org

50 pointshypnocode13 comments

Let's see what the actual journal article says.

http://www.sciencemag.org/content/337/6096/825.abstract?sid=...

Long-Range Ordered Carbon Clusters: A Crystalline Material with Amorphous Building Blocks Lin Wang, Bingbing Liu, Hui Li, Wenge Yang, Yang Ding, Stanislav V. Sinogeikin, Yue Meng, Zhenxian Liu, Xiao Cheng Zeng, and Wendy L. Mao Science 17 August 2012: 337 (6096), 825-828. [DOI:10.1126/science.1220522]

The Science editors also solicited a commentary

http://www.sciencemag.org/content/337/6096/812.summary

on the article.

AFTER EDIT:

As I read through the full-text article, it seems that the kind of nanoscale observations being reported in the article might be consistent with the "new" material simply being local, small-scale diamonds (the substrate material was carbon molecules, after all, before they were subjected to high pressure), being "as incompressible as diamond," as reported, for the unremarkable reason that it is diamond. But I will defer to someone who is more knowledgeable than I in materials science to see what other interpretation of the published article might make more sense.

Thanks for posting that!

Here is the full pdf: https://filetea.me/t1se48ed

Materials Scientist here.

There are no small-scale diamonds present in the material. On the small scale, the material is a carbon glass (an unordered, or amorphous solid), distinct from diamond, which is an ordered crystal. Typically, high density glasses are stronger than crystals made from the same elements, so the strength of the material isn't particularly surprising, rather it's the processing of the new material that is novel.

It's also worth noting that this isn't even the first carbon-based material stronger than diamond. Lonsdaleite is a closely related structure that is significantly stronger. It is much less common, however, naturally occurring only in meteorites.

Any idea as to which one is actually harder, the new material, or Lonsdaleite? I see from this journal that Lonsdaleite has 58% higher indentation strength than diamond: http://prl.aps.org/abstract/PRL/v102/i5/e055503 but I couldn't find figures for the new material.

Diamond is only the hardest known naturally occurring material.

For the hardest known material, take a look at this paper from 2005: http://adsabs.harvard.edu/abs/2005ApPhL..87h3106D

Or the Wikipedia article for a more general treatment: https://en.wikipedia.org/wiki/Aggregated_diamond_nanorod

Not even that, quite. There are two known naturally occurring minerals that are harder than diamond: wurtzite boron nitride, and lonsdaleite (another carbon allotrope). They just don't occur in very large quantities.

Ref: http://www.newscientist.com/article/dn16610-diamond-no-longe...

Actually, the title isn't wrong, it's just misleading. When you read "new form of matter", your first thought was probably liquid, gas, solid, plasma, (something new here?). However, those refer to the "state" or "phase" of matter.

Form: the shape of a thing or person.

Basically, they have "formed" a new type of matter, which is simply the way in which the atoms are arranged in thermodynamic equilibrium. They are not referring to discovering a new "state" or "phase".

Note, not a new form of matter, yet another form of carbon (of which there are bazillions) Cool result though.

From the paper's abstract:

Solid-state materials can be categorized by their structures into crystalline (having periodic translation symmetry), amorphous (no periodic and orientational symmetry), and quasi-crystalline (having orientational but not periodic translation symmetry) phases. Hybridization of crystalline and amorphous structures at the atomic level has not been experimentally observed. We report the discovery of a long-range ordered material constructed from units of amorphous carbon clusters that was synthesized by compressing solvated fullerenes.

So not a new type of matter, a new type of solid-state material, right? Or are different solid-state materials considered different forms of matter?

Scientific journalism at its worst.

Really, this is fucking ridiculous.

EDIT:

In light of some controversy over the title of this article I have taken the liberty of removing what I see as being some of the more potentially misleading terms.

The word "create" is rather obviously a misnomer based on Newtons laws, but I'm trying to stay true to the text of the original article, while keeping the discussion on the scientific merit of the subject.

Thank you.

adamantium? cheers

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