تقرير
Thermodynamics of hydrogen vacancies in MgH2 from first-principles calculations and grand-canonical statistical mechanics
العنوان: | Thermodynamics of hydrogen vacancies in MgH2 from first-principles calculations and grand-canonical statistical mechanics |
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المؤلفون: | Grau-Crespo, R., Smith, K. C., Fisher, T. S., de Leeuw, N. H., Waghmare, U. V. |
سنة النشر: | 2009 |
المجموعة: | Condensed Matter |
مصطلحات موضوعية: | Condensed Matter - Materials Science, Condensed Matter - Statistical Mechanics |
الوصف: | Ab initio calculations and statistical mechanics are combined to elucidate the thermodynamics of H vacancies in MgH2. A general method based on a grand-canonical ensemble of defect configurations is introduced to model the exchange of hydrogen between crystalline MgH2 and gas-phase H2. We find that, at temperatures and hydrogen partial pressures of practical interest, MgH2 is capable of accommodating only very small concentrations of hydrogen vacancies, which consist mainly of isolated defects rather than vacancy clusters, contrary to what is expected from a simple energetic analysis. Comment: 13 pages, 5 figures. Paper accepted in Physical Review B |
نوع الوثيقة: | Working Paper |
DOI: | 10.1103/PhysRevB.80.174117 |
URL الوصول: | http://arxiv.org/abs/0910.4331 |
رقم الأكسشن: | edsarx.0910.4331 |
قاعدة البيانات: | arXiv |
DOI: | 10.1103/PhysRevB.80.174117 |
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