Using a microscopic phenomenological model for longitudinal spin fluctuations (LSFs) based on density functional theory calculations, we demonstrate that under the Earth's core conditions ($P\approx 360$ GPa, $T\approx 6000$ K), Fe acquires substantial local magnetic moment, up to 1.3 ${\mu }_B$, for different crystal structure modifications. We demonstrate that the LSFs produce a substantial effect on the magnetic and thermodynamic properties of iron, in particular, its equilibrium volume under solid Earth's core conditions.

• Received 7 October 2012

DOI:https://doi.org/10.1103/PhysRevB.87.014405