eprintid: 1367040
rev_number: 40
eprint_status: archive
userid: 608
dir: disk0/01/36/70/40
datestamp: 2012-10-10 19:19:34
lastmod: 2021-10-04 01:18:47
status_changed: 2012-10-10 19:19:34
type: article
metadata_visibility: show
item_issues_count: 0
creators_name: Cote, AS
creators_name: Vocadlo, L
creators_name: Brodholt, JP
title: Ab initio simulations of iron-nickel alloys at Earth's core conditions
ispublished: pub
divisions: UCL
divisions: B04
divisions: C06
divisions: F57
keywords: iron, nickel, Earth's core, ab initio
note: This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
abstract: We report ab initio density functional theory calculations on iron–nickel (FeNi) alloys at conditions representative of the Earth's inner core. We test different concentrations of Ni, up to ∼39 wt% using ab initio lattice dynamics, and investigate the thermodynamic and vibrational stability of the three candidate crystal structures (bcc, hcp and fcc). First of all, at inner core pressures, we find that pure Fe transforms from the hcp to the fcc phase at around 6000 K. Secondly, in agreement with low pressure experiments on Fe–Ni alloys, we find the fcc structure is stabilised by the incorporation of Ni under core pressures and temperatures. Our results show that the fcc structure may, therefore, be stable under core conditions depending on the temperature in the inner core and the Ni content. Lastly, we find that within the quasi-harmonic approximation, there is no stability field for FeNi alloys in the bcc structure under core conditions.
date: 2012-09
official_url: http://dx.doi.org/10.1016/j.epsl.2012.06.025
vfaculties: VMPS
vfaculties: VMPS
oa_status: green
language: eng
primo: open
primo_central: open_green
verified: verified_manual
elements_source: WoS-Lite
elements_id: 524980
doi: 10.1016/j.epsl.2012.06.025
lyricists_name: Brodholt, John
lyricists_name: Cote, Alexander
lyricists_name: Vocadlo, Lidunka
lyricists_id: JPBRO15
lyricists_id: ASCOT13
lyricists_id: NLVOC18
full_text_status: public
publication: Earth and Planetary Science Letters
volume: 345-34
pagerange: 126 - 130
issn: 0012-821X
citation:        Cote, AS;    Vocadlo, L;    Brodholt, JP;      (2012)    Ab initio simulations of iron-nickel alloys at Earth's core conditions.                   Earth and Planetary Science Letters , 345-34    126 - 130.    10.1016/j.epsl.2012.06.025 <https://doi.org/10.1016/j.epsl.2012.06.025>.       Green open access   
 
document_url: https://discovery.ucl.ac.uk/id/eprint/1367040/1/1367040.pdf