title: Pure iron compressed and heated to extreme conditions.
abstract: The results of a first-principles study supported by the temperature-quenched laser-heated diamond anvil-cell experiments on the high-pressure high-temperature structural behavior of pure iron are reported. We show that in contrast to the widely accepted picture, the face-centered cubic (fcc) phase becomes as stable as the hexagonal-close-packed (hcp) phase at pressures around 300-360 GPa and temperatures around 5000-6000 K. Our temperature-quenched experiments indicate that the fcc phase of iron can exist in the pressure-temperature region above 160 GPa and 3700 K, respectively. This, in particular, means that the actual structure of the Earth's core may be a complex phase with a large number of stacking faults.
authors.affiliation: Department of Physics, Uppsala University, Box 530, SE-751 21 Uppsala, Sweden.
authors.forename: A S
authors.initials: AS
authors.lastname: Mikhaylushkin
authors.forename: S I
authors.initials: SI
authors.lastname: Simak
authors.forename: L
authors.initials: L
authors.lastname: Dubrovinsky
authors.forename: N
authors.initials: N
authors.lastname: Dubrovinskaia
authors.forename: B
authors.initials: B
authors.lastname: Johansson
authors.forename: I A
authors.initials: IA
authors.lastname: Abrikosov