Astronomers have recently wondered whether carbon might form a supercooled liquid under the huge pressures that exist in side carbon-rich white dwarf stars and even inside medium-sized gaseous planets such as neptune and uranus. If that’s the case, then small disturbances in the liquid could trigger the formation of diamonds the size of automobiles.
The trouble is that nobody has been able to create these conditions on Earth so the way in which nucleation might occur is more or less unknown.
Now Daan Frenkel and pals from the University of Amsterdam in The Netherlands say that computer simulations of the behaviour of several thousand carbon atoms under these circumstances have given us the first inkling of how nucleation occur. And the odds are that it’s a tricky process to set in motion.
Applying these results to astrophysical bodies gives two insights, both of which are bad news for diamond hunters.
First, nucleation may be so rare that “not a single diamond could have nucleated in a Uranus-sized body during the life of the universe.”
And second, the appropriate conditions may be common in certain white dwarf stars.
Either way, these diamonds are outta bounds for the foreseeable future.
Ref: arxiv.org/abs/0804.1671: State-of-the-art models for the Phase Diagram of Carbon and Diamond Nucleation