Systematic theoretical study of [001] symmetric tilt grain boundaries in MgO from 0 to 120 GPa

Abstract : The properties of [001] symmetric tilt grain boundaries (STGBs) in magnesium oxide are investigated systematically with atomic-scale simulations. Their formation energies, atomic structures, and excess volumes are computed. STGBs are found to prefer a symmetric configuration, except for tilt angles larger than 67.4°, where the decomposition of the STGBs into ½[110] dislocations is preferred. Then, the effects of pressure are investigated from 30 up to 120 GPa, a pressure range relevant to the Earth’s lower mantle. Pressure is found to change the atomic configuration of all investigated GBs, sometimes several times as pressure increases. We also find that these changes are irreversible, the GBs retaining their high-pressure configuration even after pressure is released. Implications for the deformation of ferropericlase in the conditions of the Earth’s lower mantle are discussed.
Type de document :
Article dans une revue
Liste complète des métadonnées

Littérature citée [48 références]  Voir  Masquer  Télécharger

https://hal.univ-lille.fr/hal-02091113
Contributeur : Lilloa Université de Lille <>
Soumis le : vendredi 5 avril 2019 - 14:02:02
Dernière modification le : mardi 9 avril 2019 - 01:17:17
Archivage à long terme le : samedi 6 juillet 2019 - 14:06:12

Fichier

Hirel-et-al(2019)SystematicThe...
Publication financée par une institution

Licence


Distributed under a Creative Commons Paternité 4.0 International License

Identifiants

Collections

Citation

Pierre Hirel, Gabriel Franck Bouobda Moladje, Philippe Carrez, Patrick Cordier. Systematic theoretical study of [001] symmetric tilt grain boundaries in MgO from 0 to 120 GPa. Physics and Chemistry of Minerals, Springer Verlag, 2018, 46 (1), pp.37-49. ⟨10.1007/s00269-018-0985-7⟩. ⟨hal-02091113⟩

Partager

Métriques

Consultations de la notice

34

Téléchargements de fichiers

45