The melting curve of iron at the pressures of the earth's core from ab initio calculations

ABSTRACT The solid inner core of the Earth and the liquid outer core consist mainly of iron1 so that knowledge of the high-pressure thermodynamic properties of iron is important for

understanding the Earth's deep interior. An accurate knowledge of the melting properties of iron is particularly important, as the temperature distribution in the core is relatively

uncertain2,3,4 and a reliable estimate of the melting temperature of iron at the pressure of the inner-core boundary would put a much-needed constraint on core temperatures. Here we used _ab

initio_ methods to compute the free energies of both solid and liquid iron, and we argue that the resulting theoretical melting curve competes in accuracy with those obtained from

high-pressure experiments. Our results give a melting temperature of iron of ∼6,700 ± 600 K at the pressure of the inner-core boundary, consistent with some of the experimental measurements.

Our entirely _ab initio_ methods should also be applicable to many other materials and problems. Access through your institution Buy or subscribe This is a preview of subscription content,

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OPTIONS: * Log in * Learn about institutional subscriptions * Read our FAQs * Contact customer support SIMILAR CONTENT BEING VIEWED BY OTHERS EARTH’S CORE COULD BE THE LARGEST TERRESTRIAL

CARBON RESERVOIR Article Open access 19 August 2021 HEAVY IRON ISOTOPE COMPOSITION OF IRON METEORITES EXPLAINED BY CORE CRYSTALLIZATION Article 03 August 2020 LIGHT ELEMENTS IN THE EARTH’S

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ACKNOWLEDGEMENTS The calculations were run on the Cray T3E machines at Manchester CSAR Centre and the Edinburgh Parallel Computer Centre. We thank L. Vočadlo for discussions. AUTHOR

INFORMATION AUTHORS AND AFFILIATIONS * Research School of Geological and Geophysical Sciences, Birkbeck College and University College London, Gower Street, London, WC1E 6BT, UK D. Alfè 

& G. D. Price * Physics and Astronomy Department University College London, Gower Street, London , WC1E 6BT, UK M. J. Gillan Authors * D. Alfè View author publications You can also

search for this author inPubMed Google Scholar * M. J. Gillan View author publications You can also search for this author inPubMed Google Scholar * G. D. Price View author publications You

can also search for this author inPubMed Google Scholar CORRESPONDING AUTHOR Correspondence to D. Alfè. RIGHTS AND PERMISSIONS Reprints and permissions ABOUT THIS ARTICLE CITE THIS ARTICLE

Alfè, D., Gillan, M. & Price, G. The melting curve of iron at the pressures of the Earth's core from _ ab initio_ calculations. _Nature_ 401, 462–464 (1999).

https://doi.org/10.1038/46758 Download citation * Received: 06 May 1999 * Accepted: 03 August 1999 * Issue Date: 30 September 1999 * DOI: https://doi.org/10.1038/46758 SHARE THIS ARTICLE

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