Skip to Main content Skip to Navigation
Journal articles

Sound velocities and thermodynamical properties of hcp iron at high pressure and temperature

Abstract : Sound velocities and thermodynamical properties of hcp iron have been computed using ab initio calculations over an extended density and temperature range, encompassing the conditions directly relevant for the Earth's inner core. At room temperature, and up to 350 GPa, an excellent agreement is obtained between present results and experimental data for many thermodynamical quantities: phonon density of states, vibrational entropy, heat capacity, Grüneisen parameter and thermal expansion. With increasing temperature, along an isochore, we observe a strong decrease of the phonon frequencies, demonstrating that intrinsic anharmonic effects cannot be neglected. We also carefully compare previous theoretical data for the sound velocities and try to explain the discrepancies observed with experiments. Finally, we propose a temperature dependant Birch's law that we compare with previous experimental work
Complete list of metadata

https://hal.archives-ouvertes.fr/hal-03703963
Contributor : Guillaume Morard Connect in order to contact the contributor
Submitted on : Friday, June 24, 2022 - 2:30:31 PM
Last modification on : Thursday, July 7, 2022 - 3:21:35 AM

File

 Restricted access
To satisfy the distribution rights of the publisher, the document is embargoed until : 2022-12-24

Please log in to resquest access to the document

Identifiers

Citation

Johann Bouchet, Francois Bottin, Daniele Antonangeli, Guillaume Morard. Sound velocities and thermodynamical properties of hcp iron at high pressure and temperature. Journal of Physics: Condensed Matter, IOP Publishing, 2022, 34 (34), pp.344002. ⟨10.1088/1361-648x/ac792f⟩. ⟨hal-03703963⟩

Share

Metrics

Record views

10