| Autor: |
Swinburne TD; CCFE, Culham Science Centre, Abingdon, Oxon OX14 3DB, United Kingdom., Marinica MC; DEN-Service de Recherches de Métallurgie Physique, CEA, Université Paris-Saclay, F-91191 Gif-sur-Yvette, France. |
| Jazyk: |
angličtina |
| Zdroj: |
Physical review letters [Phys Rev Lett] 2018 Mar 30; Vol. 120 (13), pp. 135503. |
| DOI: |
10.1103/PhysRevLett.120.135503 |
| Abstrakt: |
The calculation of free energy differences for thermally activated mechanisms in the solid state are routinely hindered by the inability to define a set of collective variable functions that accurately describe the mechanism under study. Even when possible, the requirement of descriptors for each mechanism under study prevents implementation of free energy calculations in the growing range of automated material simulation schemes. We provide a solution, deriving a path-based, exact expression for free energy differences in the solid state which does not require a converged reaction pathway, collective variable functions, Gram matrix evaluations, or probability flux-based estimators. The generality and efficiency of our method is demonstrated on a complex transformation of C15 interstitial defects in iron and double kink nucleation on a screw dislocation in tungsten, the latter system consisting of more than 120 000 atoms. Both cases exhibit significant anharmonicity under experimentally relevant temperatures. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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