Quasihydrostatic equation of state of iron above 2 Mbar

Phys Rev Lett. 2006 Nov 24;97(21):215504. doi: 10.1103/PhysRevLett.97.215504. Epub 2006 Nov 22.


The compression curve of iron is measured up to 205 GPa at 298 K, under quasihydrostatic conditions in a diamond anvil cell. Above 150 GPa, the compression of this metal is significantly higher than previously measured under nonhydrostatic conditions. The same compression curve is also calculated ab initio and the deviation between experiment and theory is clearly established. A formulation of the equation of state of iron over a large pressure and temperature range, based on the current data and existing shock-wave data, is also proposed. Implications for the Earth's core are discussed.