Anharmonic thermodynamics of vacancies using a neural network potential
| Autor: | Stefano Mossa, Anton S. Bochkarev, Ambroise van Roekeghem, Natalio Mingo |
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| Přispěvatelé: | CEA Grenoble (CEA), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), ANR-18-CE30-0019,HEATFLOW,Transport thermique dans les solides, au delà de l'approximation classique(2018) |
| Rok vydání: | 2019 |
| Předmět: |
Materials science
Physics and Astronomy (miscellaneous) FOS: Physical sciences Thermodynamics 02 engineering and technology 01 natural sciences Condensed Matter::Materials Science symbols.namesake Vacancy defect 0103 physical sciences Physics::Atomic and Molecular Clusters General Materials Science Physics::Chemical Physics 010306 general physics ComputingMilieux_MISCELLANEOUS Arrhenius equation Condensed Matter - Materials Science Artificial neural network Anharmonicity Materials Science (cond-mat.mtrl-sci) 021001 nanoscience & nanotechnology Nonlinear system [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci] symbols Density functional theory Free energies 0210 nano-technology |
| Zdroj: | Physical Review Materials Physical Review Materials, American Physical Society, 2019, 3 (9), ⟨10.1103/PhysRevMaterials.3.093803⟩ Physical Review Materials, 2019, 3 (9), ⟨10.1103/PhysRevMaterials.3.093803⟩ |
| ISSN: | 2475-9953 |
| DOI: | 10.1103/physrevmaterials.3.093803 |
| Popis: | Lattice anharmonicity is thought to strongly affect vacancy concentrations in metals at high temperatures. It is however non-trivial to account for this effect directly using density functional theory (DFT). Here we develop a deep neural network potential for aluminum that overcomes the limitations inherent to DFT, and we use it to obtain accurate anharmonic vacancy formation free energies as a function of temperature. While confirming the important role of anharmonicity at high temperatures, the calculation unveils a markedly nonlinear behavior of the vacancy formation entropy and shows that the vacancy formation free energy only violates Arrhenius law at temperatures above 600 K, in contrast with previous DFT calculations. |
| Databáze: | OpenAIRE |
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