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Zobelli, A., Ewels, C. P., Gloter, A. & Seifert, G. (2007) Vacancy migration in hexagonal boron nitride. Phys. Rev. B, 75 094104.
Added by: Laurent Cournède (2016-03-10 22:02:31) |
| Type de référence: Article DOI: 10.1103/PhysRevB.75.094104 Numéro d'identification (ISBN etc.): 1098-0121 Clé BibTeX: Zobelli2007a Voir tous les détails bibliographiques  |
Catégories: PMN Mots-clés: bn, construction, Defects, elastic band method, graphite, minimum energy paths, nanotubes, nitrogen analogs, saddle-points, semiconductors Créateurs: Ewels, Gloter, Seifert, Zobelli Collection: Phys. Rev. B |
Consultations : 1/605
Indice de consultation : 4% Indice de popularité : 1% |
| Résumé |
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Activation energies and reaction paths for diffusion and nucleation of mono- and divacancy defects in hexagonal boron nitride layers are theoretically investigated. Migration paths are derived using the nudged elastic band method combined with density-functional-based techniques. We find a different behavior for migration of single boron and nitrogen vacancies with the existence of intermediate metastable states along the migration paths. The temperature dependence of entropic and vibrational contributions to the free Gibbs energies is explicitly taken in account. A rich phase diagram for vacancy migration is then obtained. Boron vacancies are first thermally activated and can migrate to form more stable BN divacancies. At high temperatures, the divacancies can further be activated. In the contrary, nitrogen vacancy migration is energetically unfavorable within all the temperature range below the melting point of h-BN.
Added by: Laurent Cournède |