A Sandia supercomputer simulation model called SNAP, or Spectral Neighbor Analysis Potential, that rapidly predicts the behavior of billions of interacting atoms has captured the melting of diamond when compressed by extreme pressures and temperatures.
At several million atmospheres, the rigid carbon lattice of the hardest known substance on Earth is shown in SNAP simulations to crack, melt into amorphous carbon and then recrystallize. The work could aid understanding of the internal structure of carbon-based exoplanets and have important implications for nuclear fusion efforts that employ capsules made of polycrystalline diamond.
“We can now study the response of many materials under the same extreme pressures,” said Sandia scientist Aidan Thompson, who originated SNAP. “Applications include planetary science questions — for example, what kind of impact stress would have led to formation of our moon? It also opens the door to design and manufacture of novel materials at extreme conditions.”