Are homemade diamonds girl's new best friend?

Plazma Inferno!

Plazma Inferno!

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A new phase of solid carbon, called Q-Carbon, distinct from the known phases of graphite and diamond, has been discovered by researchers. It is ferromagnetic, harder than diamond, and glows when exposed to even low levels of energy.
And the most important, Q-carbon could be used to make diamond-related structures at room temperature and at ambient atmospheric pressure in air.
http://phys.org/news/2015-11-phase-carbon-diamond-room-temperature.html

So, are DIY diamonds possible? And would such diamonds be useful for proposals, i.e. what is the difference to real diamonds?
 
Plazma Inferno! said:
A new phase of solid carbon, called Q-Carbon, distinct from the known phases of graphite and diamond, has been discovered by researchers. It is ferromagnetic, harder than diamond, and glows when exposed to even low levels of energy.
And the most important, Q-carbon could be used to make diamond-related structures at room temperature and at ambient atmospheric pressure in air.
http://phys.org/news/2015-11-phase-carbon-diamond-room-temperature.html

So, are DIY diamonds possible? And would such diamonds be useful for proposals, i.e. what is the difference to real diamonds?
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How frustrating that there is no information in this link about the structure and bonding of this allotrope - if that is what it really turns out to be. Presumably there are unpaired electrons, since it is ferromagnetic. Or can the magnetism arise in some strange new way from "ring currents" in the pi-bonding of hexagonal rings of carbon, such as one typically gets in graphite? So what is its structure?

Also it is frustrating that the article speaks of this material glowing when exposed to "low levels of energy". What does this mean? Are they talking of thermal energy, or of illuminating it with light, i.e. a form of fluorescence? If the latter, then does low energy mean low energy photons, e.g. infra red or microwave, or do they simply mean low intensity of illumination?

As for making "diamond-like structures", the way I read it is that these are very small crystals indeed.
 
So they vapor-deposited thin films of glassy carbon and zaps those thin films with lasers whereupon they got droplets of 4000K liquid carbon near normal air pressure which froze up as nanodiamonds because the low pressure liquid carbon had tiny bits of diamond-like carbon and the cold (relative to the normal 5000K melting point of carbon) liquid didn't have the time to form graphite sheets?
 
sweetpea said:
There seems to be more information here...
http://scitation.aip.org/content/aip/journal/aplmater/3/10/10.1063/1.4932622
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Thanks for digging this out - evidently one of the authors is the same. But this paper does not seem to have anything about ferromagnetism or fluorescence, which are the phenomena of interest to me as a chemist (Personally I don't give a stuff about making diamonds this way: I do not believe there is any point in dreaming of making gemstones more cheaply than you can dig them up from volcanic pipes:smile:).
 
They say that not even jewelers can't identify fake diamonds today because they are so well made. So why buy a real one when you can get away with buying a fake one? If no one can tell what you are wearing wouldn't it be prudent to only wear fake ones in case you are held up? So why pay outrageous prices for "rocks" when you could save thousands buying fake gems.
 
Plazma Inferno! said:
So, are DIY diamonds possible? And would such diamonds be useful for proposals, i.e. what is the difference to real diamonds?
Click to expand...

DIY/homemade diamonds are probably a while away; what is the energy demand for achieving 4,000K? Additionally, it would seem safety would present an expensive challenge.

And while it is possible a market will eventually emerge, one can only wonder at how the traditional diamond market would react.

And, in the end, if Q-diamonds become so accessible, will they have the same significance?

A boatload of diamonds at Krakatoa? Okay, that's an obscure joke.
 
cosmictraveler said:
They say that not even jewelers can't identify fake diamonds today because they are so well made. So why buy a real one when you can get away with buying a fake one? If no one can tell what you are wearing wouldn't it be prudent to only wear fake ones in case you are held up? So why pay outrageous prices for "rocks" when you could save thousands buying fake gems.
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Tiassa said:
And, in the end, if Q-diamonds become so accessible, will they have the same significance?
Click to expand...
My thoughts exactly. What would be the significance of real diamonds if we could have perfect "fakes" or man-made alternatives.
 
spidergoat said:
For one thing you can make them flawless. And large. And not dig up tons of soil.
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Yeah yeah, I'll believe it when I see it.

I just do not believe anyone will be able to turn this sort of process into a commercial gem-making operation that is competitive.
 
exchemist said:
Yeah yeah, I'll believe it when I see it.

I just do not believe anyone will be able to turn this sort of process into a commercial gem-making operation that is competitive.
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Ooh, tough question. Since there has long been a near monopoly on consumer gem-quality cut diamonds, it's difficult to say what the price of diamonds should be.

But as of 2013, synthetic diamonds represented about 2% of gem sales (by weight). (about 840,000 carats) http://www.kitco.com/ind/Zimnisky/2...ynthetic-Diamonds-Will-Impact-the-Market.html
The record then was a 1.29 carat synthetic stone priced at a 38% discount relative to a mined and cut stone of similar quality.

3 carat stones have debuted at a 42% discount. https://www.washingtonpost.com/post...252a02-b2f3-11e4-bf39-5560f3918d4b_video.html (video)

But this year, we have stones of 4 carats, 5 carat and now a 10.02 carat stone of quality was produced. http://www.jckonline.com/2015/05/27/company-grows-10-carat-synthetic-diamond

As this is an engineered manufacturing process, it has a capability of being tuned for market conditions while the mined-diamond monopolies can rely partly on their carefully throttled inventory and marketing campaigns to try and tune the market. It is the former, not the latter which looks more sustainable to me so I expect the price of all gem diamonds to fall in the future.

(Two links taken from: https://en.wikipedia.org/wiki/Synthetic_diamond#Gemstones )
 
rpenner said:
As this is an engineered manufacturing process, it has a capability of being tuned for market conditions while the mined-diamond monopolies can rely partly on their carefully throttled inventory and marketing campaigns to try and tune the market. It is the former, not the latter which looks more sustainable to me so I expect the price of all gem diamonds to fall in the future.
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If synthetic diamonds threaten mined-diamond monopolies, that's good went it comes to the medical use of diamonds isn't it?
http://www.sciencedirect.com/science/article/pii/S1369702111700876#
Diamond has been considered for use in several medical applications due to its unique mechanical, chemical, optical, and biological properties. In this paper, methods for preparing synthetic diamond surfaces and particles are described. In addition, recent developments involving the use of diamond in prostheses, sensing, imaging, and drug delivery applications are reviewed. These developments suggest that diamond-containing structures will provide significant improvements in the diagnosis and treatment of medical conditions over the coming years.
Click to expand...
 
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rpenner said:
Ooh, tough question. Since there has long been a near monopoly on consumer gem-quality cut diamonds, it's difficult to say what the price of diamonds should be.

But as of 2013, synthetic diamonds represented about 2% of gem sales (by weight). (about 840,000 carats) http://www.kitco.com/ind/Zimnisky/2...ynthetic-Diamonds-Will-Impact-the-Market.html
The record then was a 1.29 carat synthetic stone priced at a 38% discount relative to a mined and cut stone of similar quality.

3 carat stones have debuted at a 42% discount. https://www.washingtonpost.com/post...252a02-b2f3-11e4-bf39-5560f3918d4b_video.html (video)

But this year, we have stones of 4 carats, 5 carat and now a 10.02 carat stone of quality was produced. http://www.jckonline.com/2015/05/27/company-grows-10-carat-synthetic-diamond

As this is an engineered manufacturing process, it has a capability of being tuned for market conditions while the mined-diamond monopolies can rely partly on their carefully throttled inventory and marketing campaigns to try and tune the market. It is the former, not the latter which looks more sustainable to me so I expect the price of all gem diamonds to fall in the future.

(Two links taken from: https://en.wikipedia.org/wiki/Synthetic_diamond#Gemstones )
Click to expand...


Thank you very much for this. I've done more reading around the subject now and it seems synthetic gem diamonds are indeed not just a pipe dream. So I was wrong and I've learnt something. The Russians seem particularly interested in this, it seems.
 
exchemist said:
Thank you very much for this. I've done more reading around the subject now and it seems synthetic gem diamonds are indeed not just a pipe dream. So I was wrong and I've learnt something. The Russians seem particularly interested in this, it seems.
Click to expand...
You are welcome.

On a different note, the second article is now online:

http://scitation.aip.org/content/aip/journal/jap/118/21/10.1063/1.4936595

After skimming both articles, is unclear where the assertion that Q-carbon "glows when exposed to even low levels of energy" comes from. But this paper has support for "it is ferromagnetic" and "is harder than diamond".
 
rpenner said:
You are welcome.

On a different note, the second article is now online:

http://scitation.aip.org/content/aip/journal/jap/118/21/10.1063/1.4936595

After skimming both articles, is unclear where the assertion that Q-carbon "glows when exposed to even low levels of energy" comes from. But this paper has support for "it is ferromagnetic" and "is harder than diamond".
Click to expand...

Aha, many thanks for this link. They say Q carbon has a mixture of sp3 and sp2 hybridised carbon, resulting from its strange structure. This is a matrix of amorphous sp3 carbon with "nano" diamond structures - also sp3 - embedded within it. But these nano-scale portions of diamond structure are only of the order of 10nm, i.e ~100 atoms long, on a side, so (this is now my interpolation) quite a high proportion of the material consists of the transitional boundary regions between these two types of structure. At these boundaries between the phases, they say there are sp2 (graphite type) hybridised carbon, some of which is sterically strained (the geometry of neighbouring atoms is not at the 120 deg angles needed for an unstrained sp2 structure). They say about 20% is sp2 and the rest sp3.

Sp2 hybridisation would normally give the "pi bonding" one gets in benzene and "aromatic" fused rings of carbon, up to and including Buckminsterfullerene and graphite. This results from overlap of atomic p orbitals, perpendicular to the plane of the sp2 sigma bonds, giving rise to molecular "pi" orbitals lying above and below the plane. But, and this is I suspect is the exciting bit, when you have isolated sp2 atoms each with an unpaired electron and they are too far apart to overlap properly, you have unpaired p electrons. And unpaired electrons are what you need for ferromagnetism. Bingo!

I suppose it may also be that with a range of sterically strained atoms, the energy levels of these orbitals may spread out into a band, rather than being nicely aligned in energy. Possibly this has consequences for the way molecular orbitals are constructed and the resulting energy gaps between ground and excited states. Maybe the explanation for the fluorescence, or whatever it is, is somehow connected with this, but indeed the paper does not say.

But now I begin to see what they have done and how magnetism arises from it. I must say I am impressed with the amount of structural characterisation they seem to have managed.
 
Tiassa said:
DIY/homemade diamonds are probably a while away; what is the energy demand for achieving 4,000K? Additionally, it would seem safety would present an expensive challenge.

And while it is possible a market will eventually emerge, one can only wonder at how the traditional diamond market would react.

And, in the end, if Q-diamonds become so accessible, will they have the same significance?

A boatload of diamonds at Krakatoa? Okay, that's an obscure joke.
Click to expand...
It seems the composition and properties make them as significant as mined diamonds. If a jeweler can't tell the difference then your wife probably can't either. I agree,with rpenner, that the cost of a diamond will be reduced significantly. This is a good thing.
 
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