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arXiv · 1702.04660

Ab initio based empirical potential applied to tungsten at high pressure

Robert C. Ehemann·Jeremy W. Nicklas·Hyoungki Park·John W. Wilkins
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Abstract

Density-functional theory forces, stresses and energies comprise a database from which the optimal parameters of a spline-based empirical potential combining Stillinger-Weber and modified embedded-atom forms are determined. Accuracy of the potential is demonstrated by predictions of ideal shear, stacking fault, vacancy migration, elastic constants and phonons all between 0 and 100 GPa. Consistency with existing models and experiments is demonstrated by application to screw dislocation core structure and deformation twinning in a tungsten nanorod. Lastly, the potential is used to study the high-pressure bcc to fcc phase transition.

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Robert C. Ehemann, Jeremy W. Nicklas, Hyoungki Park, John W. Wilkins. 2017-02-15. Ab initio based empirical potential applied to tungsten at high pressure. https://doi.org/10.1103/physrevb.95.184101

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