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Posted

After reading about how to form diamonds from charcoal, peanut butter, and a microwave, I got to thinking about REAL ways to form a diamond :phones:.

 

Now, I've recently had an interest in the extreme heat created by a thermite reaction, and what greater uses it may have. I speculated the heat may be useful in forming some sort of compound. Tonight I thought of diamonds. Did a quick search and found that the first creators of artificial diamonds had indeed used thermite reactions to produce enough heat to form diamonds from graphite (with great pressure included). Getting close. Now, if we are to assume the equation will always be heat + pressure + carbon = diamond, isn't it physically possible for one of the variables in the equation to be replaced with something of greater or equal value?

 

MY thought is on replacing the pressure requirement with a resonance or vibration that would fascilitate the crystalization of carbon out of a high heat thermite reaction. I had heard it speculated (by the first artificial diamond creators I think) that a high presence of carbon in the molten themrite reaction would naturally force the metal to phase out the carbon as a crystal under high pressure. Perhaps a carbon crystal of diamond can be formed in much the same way if it were aided by the vibration/resonance of a diamond, or something that fascilitates the carbon to structure itself into a crystaline diamond? Isn't there some sort of physics that might support this theory?

Posted

a buddy of mine wrote:

 

Original diamond-synthesis programmes used graphite and extreme pressures, and when I say extreme, I really mean it - we're taking as hot as the surface of the sun and several gigapascals of pressure (100,000 atmospheres). This method is almost uncontrollable in terms of creating uniform diamonds.

 

The problem with the question is a misunderstanding of carbon chemistry and chemistry as a whole.

 

Both diamond and graphite are "crystallised" carbon, and graphite is more thermodynamically stable, in fact diamond at room temperature and atmospheric pressure will slowly convert into graphite (it is slow because the energy barrier is large, making it kinetically unfavourable, but it is a thermodynamically favourable reaction so it does happen) - any vibration that you might be interring through the reaction would naturally facilitate graphite formation over diamond.

 

The pressure is needed to make the graphite the less thermodynamically stable allotrope.

 

 

 

For an analogy - you want to turn steam into ice without making water in the middle - this is possible, but only under non-atmospheric pressures (in this case, lower pressures).

 

No amount of vibration of gaseous water molecules will make them turn spontaneously into ice crystals without using the required pressure - in fact the vibration is more likely to disrupt the ice crystals and turn them back into gases.

 

The same could be said of "crystallising" carbon atoms out of a thermite melt.

 

 

Anyway, gemstone diamonds aren't actually all that valuable, 4 times as many diamonds are synthesised than are mined. Synthesised diamonds are mostly used in making diamond coatings using Chemical Vapour Deposition, which makes diamonds out of methane and hydrogen at relatively low temperatures and pressures, and is actually quite easy to do, hence diamond-coated razor blades and diamond-coated kitchen knives.

 

Only a small fraction of the diamonds made in the world go into gems.

Posted

HIGH SCHOOL DIAMOND PROJECT

speculative technical readout

 

MY thought is on replacing the pressure requirement with a resonance or vibration that would fascilitate the crystalization of carbon out of a high heat thermite reaction.

 

"Das ist nicht nur nicht richtig, es ist nicht einmal falsch!" Wolfgang Pauli You can get any sustained bulk temp you like below ~5000 C with an ohmic resistance, an induction coil, or a plasma arc. So? Look up the literature before you attempt to rewrite empirical reality.

Posted

speculative technical readout

 

MY thought is on replacing the pressure requirement with a resonance or vibration that would fascilitate the crystalization of carbon out of a high heat thermite reaction.

 

"Das ist nicht nur nicht richtig, es ist nicht einmal falsch!" Wolfgang Pauli You can get any sustained bulk temp you like below ~5000 C with an ohmic resistance, an induction coil, or a plasma arc. So? Look up the literature before you attempt to rewrite empirical reality.

 

? Wolfgang Pauli? And I don't speak German. I was simply asking if there are any currently known laws of physics that would support such a thing.

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