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RESEARCH PRODUCT
Stability and nature of the volume collapse of ε-Fe2O3 under extreme conditions
M. MonteVera CuarteroVirginia MonteseguroMartí GichAlfonso MuñozGaston GarbarinoTetsuo IrifuneTetsuo IrifuneValerio CerantolaJuan Angel SansCatalin Popescusubject
PHASE-TRANSFORMATIONEquation of stateMaterials scienceXRDScienceSILICATEIron oxideIRON(III) OXIDEGeneral Physics and Astronomy02 engineering and technology01 natural sciencesGeneral Biochemistry Genetics and Molecular BiologyMantle (geology)ArticlePhysics::Geophysicschemistry.chemical_compoundCondensed Matter::Materials ScienceX-RAY-DIFFRACTIONMAGNETIC PHASESpin crossoverPhase (matter)synchrotron0103 physical sciences[CHIM]Chemical SciencesCRYSTAL-STRUCTUREe-Fe2O3010306 general physicslcsh:ScienceMultidisciplinaryMössbauer spectroscopyIRONQIron(III) oxideSPIN-CROSSOVERGeneral Chemistry021001 nanoscience & nanotechnologySilicateTHERMAL-DECOMPOSITIONEXAFShigh pressureFE2O3 POLYMORPHdiamond anvil cellchemistry13. Climate actionChemical physicslcsh:Q0210 nano-technologyEarth (classical element)description
Iron oxides are among the major constituents of the deep Earth’s interior. Among them, the epsilon phase of Fe2O3 is one of the less studied polymorphs and there is a lack of information about its structural, electronic and magnetic transformations at extreme conditions. Here we report the precise determination of its equation of state and a deep analysis of the evolution of the polyhedral units under compression, thanks to the agreement between our experiments and ab-initio simulations. Our results indicate that this material, with remarkable magnetic properties, is stable at pressures up to 27 GPa. Above 27 GPa, a volume collapse has been observed and ascribed to a change of the local environment of the tetrahedrally coordinated iron towards an octahedral coordination, finding evidence for a different iron oxide polymorph.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2018-11-01 | Nature Communications |