Naked Science Forum

Non Life Sciences => Chemistry => Topic started by: Seany on 17/04/2007 11:34:07

Title: Can Diamonds be melted to liquid?
Post by: Seany on 17/04/2007 11:34:07
Can Diamonds be melted to liquid? It isn't a metal, like Gold, it's merely a pretty rock - Well I think so.

So can it be melted to a liquid? And would it have the same properties as a diamond, except for the fact that it is now a liquid?

If so, what are the melting points?
Title: Can Diamonds be melted to liquid?
Post by: paul.fr on 17/04/2007 12:25:29
not sure if you can, but seeing as diamonds are made of carbon and to be a diamond the carbon atoms have to be in a special order or stacking relative to each other. 

if you melt a diamond the carbon atoms are no longer in this special order and when it cools back down they do not return to the original stacking.

There are other forms of carbon, such as graphite and amorphous carbon.  Most likely you would end up with amorphous carbon.


Title: Can Diamonds be melted to liquid?
Post by: lightarrow on 17/04/2007 14:24:43
Can Diamonds be melted to liquid? It isn't a metal, like Gold, it's merely a pretty rock - Well I think so.
So can it be melted to a liquid?
Yes, at T > 4000°C and P ≈ 200 atm, at least according Fig. 10.14 in this document:
http://edu.sm.chim.unifi.it/prs/CFA/fig10.pdf
The temperature depends on the pressure. For example, to melt it at 2000 °C you need ≈ 500,000 atm!
Quote
And would it have the same properties as a diamond, except for the fact that it is now a liquid?
Absolutely not, as all liquids are completely different from the corresponding solids. Just think about all the optical properties that depends upon the cristalline structure (which you don't have anylonger in the liquid).
Title: Can Diamonds be melted to liquid?
Post by: Seany on 17/04/2007 15:09:59
Hmm.. Thanks Light.