First principles study of oxygen diffusion in aα-alumina twin grain boundary

Autor:	Tetsuya Tohei, Naoya Shibata, Tsubasa Nakagawa, Yuichi Ikuhara, Yuito Watanabe, Nobuaki Takahashi
Rok vydání:	2015
Předmět:	Crystallography Molecular dynamics Chemistry Boundary (topology) Grain boundary diffusion coefficient Effective diffusion coefficient Oxygen diffusion chemistry.chemical_element Grain boundary Structured model Condensed Matter Physics Molecular physics Oxygen
Zdroj:	Philosophical Magazine. 95:3985-3999
ISSN:	1478-6443 1478-6435
DOI:	10.1080/14786435.2015.1110257
Popis:	We have investigated atomistic scale behaviour of oxygen diffusion along the twin grain boundary in α-Al2O3 (alumina) using molecular dynamics simulation and first principles total energy calculations. Based on the GB structure model which is verified by atomic-scale STEM observations on the bicrystal sample, quantitative evaluation of migration energies for dominant migration paths were performed by atomistic calculations. The preset calculation results confirmed fast oxygen diffusion behaviour along the GB. Our analysis shows that the dominant migration path or difference in the migration energies can be well correlated with the geometry of local atomic coordination around the migrating oxygen; lower migration energies are generally expected for paths with less change in coordination environment on migration. This trend holds both among gain boundary paths and bulk paths in α-alumina examined in the present study.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::9dba08bbdc2cde80788310f5d5cf99c5 https://doi.org/10.1080/14786435.2015.1110257 Zobrazit plný text záznamu