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June 23, 2006

Precise atomic computations for thousands of atoms

This let us know that in order to simulate precisely thousands of atoms it takes about 200 teraflops.
(maybe if they were not under high pressure it would be less)
So for the simulations needed to determine the all of the steps for molecular manufacturing it would be good to have access to a lot more computing power.

Qbox is the most computationally intensive computer program ever developed. It has been put to work simulating the quantum behaviour of atoms.

The enhanced version of Qbox, however, reaches a sustained performance of 207.3 teraflops, a record for any software. It simulates interactions between 1000 molybdenum atoms under high pressure using equations that take the quantum behaviour of electrons into account.

Other software can be used to simulate interactions between billions of atoms, but only using classical molecular dynamics. Performing simulations involving quantum-mechanical behaviour is far more complex and, until now, such quantum simulations have only involved about 50 atoms at a time.

The molybdenum simulations will help physicists determine the reliability and stability of warheads in the US stockpile, some of which are now beyond their original storage-time limit.

But Dimitri Kusnezov, head of computing at NNSA, thinks the project could also have important scientific spin-offs, for example, helping materials scientists understand the fundamental properties of materials.

"The combination of this code and this computer has implications for the broad research community well beyond NNSA’s mission of stockpile science," he says.

1 comments:

Andrey Khavryuchenko said...

What's the point of that calculation? Waste CPU time? Justify HPC costs?

Our group predicted magnetic properties of Si (111) 7*7 surface more than 10 years ago (in '95) using mere Sun SparcStation 10. The kind of one, collecting dust on my shelf now.

This performance table states that is was just about 22 Megaflops.

207 TFlops divided by 22 MFlops gives me about 10**7 = 10 million times more powerful computational facilities. And what, calculating yes the same 1000 atoms?

Sorry, couldn't resist.