Title :

Complexions and stoichiometry of the 60.8°//[100](011) symmetrical tilt grain boundary in Mg2SiO4 forsterite: a combined empirical potential and first-principles study

Author(s) :

Furstoss, Jean [Auteur]
Unité Matériaux et Transformations (UMET) - UMR 8207
Hirel, Pierre [Auteur]
Unité Matériaux et Transformations (UMET) - UMR 8207
Carrez, Philippe [Auteur]
Unité Matériaux et Transformations (UMET) - UMR 8207
Cordier, Patrick [Auteur]
Unité Matériaux et Transformations (UMET) - UMR 8207

Journal title :

American Mineralogist

Publication date :

2022-04-13

ISSN :

0003-004X

HAL domain(s) :

Physique [physics]/Matière Condensée [cond-mat]/Science des matériaux [cond-mat.mtrl-sci]
Planète et Univers [physics]/Sciences de la Terre

English abstract : [en]

In this work we explore the low energy complexions of the symmetrical tilt grain boundary (GB) 60.8°//[100](011) in forsterite through molecular dynamics and first principles calculations. Using conservative sampling, we ...
Show more >In this work we explore the low energy complexions of the symmetrical tilt grain boundary (GB) 60.8°//[100](011) in forsterite through molecular dynamics and first principles calculations. Using conservative sampling, we find six stoichiometric complexions with energies ranging from 0.66 to 1.25 J.m−2. We investigate the segregation of MgO vacancy pairs, and find that in most cases it is more favorable for vacancies to lie within the GBs than in the surrounding crystals, leading to new atomic structures. From these results we infer that at finite temperature when vacancies are present in the system, GBs are likely to absorb them and to be non-stoichiometric. We find many GB complexions containing a free oxygen ion, which may have profound implications for geological processes.Show less >

Language :

Anglais

Peer reviewed article :

Oui

Audience :

Internationale

Popular science :

Non

European Project :

Rheology of Earth materials: closing the gap between TIMEscales in the laboratory and in the MANtle

Administrative institution(s) :

Université de Lille
CNRS
INRAE
ENSCL

Collections :

• Unité Matériaux et Transformations (UMET) - UMR 8207

Research team(s) :

Plasticité

Submission date :

2022-05-09T16:08:40Z
2022-05-10T15:25:45Z
2022-11-07T15:04:53Z
2022-11-07T15:07:15Z