LLNL: Quantum simulations of hydrogen’s phase transitions
Posted: Thu Jun 24, 2010 2:52 pm
Quantum simulations uncover hydrogen’s phase transitions
Lawrence Livermore National Laboratory | 23 June 2010
Lawrence Livermore National Laboratory | 23 June 2010
Evidence for a first-order liquid-liquid transition in high-pressure hydrogen from ab initio simulationsHydrogen is the most abundant element in the universe and is a major component of giant planets such as Jupiter and Saturn.
But not much is known about what happens to this abundant element under high-pressure conditions when it transforms from one state to another.
Using quantum simulations, scientists at the Lawrence Livermore National Laboratory, the University of Illinois at Urbana-Champaign and the University of L’Aquia in Italy were able to uncover these phase transitions in the laboratory similar to how they would occur in the centers of giant planets.
...
They discovered a first order phase transition, a discontinuity, in liquid hydrogen between a molecular state with low conductivity and a highly conductive atomic state. The critical point of the transition occurs at high temperatures, near 3100 degrees Fahrenheit and more than 1 million atmospheres of pressure.
...
There is a liquid-liquid-solid multiphase coexistence point in the hydrogen phase diagram that corresponds to the intersection of the liquid-liquid phase transition, according to a paper appearing online in the Proceedings of the National Academy of Sciences.
- Proceedings of the National Academy of Sciences, 21 June 2010, DOI: 10.1073/pnas.1007309107