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arXiv · 2304.13962

Influence of oxygen on electronic correlation and transport in iron in the outer Earth's core

German G. Blesio·Leonid V. Pourovskii·Markus Aichhorn·Monica Pozzo·Dario Alfè·Jernej Mravlje
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Abstract

Knowing the transport properties of iron under realistic conditions present in the Earth's core is essential for the geophysical modeling of Earth's magnetic field generation. Besides by extreme pressures and temperatures, transport may be influenced importantly also by the presence of light elements. Using a combination of molecular dynamics, density functional theory, and dynamical mean-field theory methods we investigate how oxygen impurities influence the electronic correlations and transport in the liquid outer Earth's core. We consider a case with an oxygen content of ~10 atomic%, a value that is believed to be close to the composition of the core. We find that the electronic correlations are enhanced but their effect on conductivities is moderate (compared to pure Fe, electrical conductivity drops by 10% and thermal conductivity by 18%). The effect of electron-electron scattering alone, whereas not large, is comparable to effects of the compositional disorder. We reveal the mechanism behind the larger suppression of the thermal conductivity and associated reduction of the Lorenz ratio and discuss its geophysical significance.

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German G. Blesio, Leonid V. Pourovskii, Markus Aichhorn, Monica Pozzo, Dario Alfè, Jernej Mravlje. 2023-04-27. Influence of oxygen on electronic correlation and transport in iron in the outer Earth's core. https://doi.org/10.1038/s43247-024-01947-x

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