A Hybrid, Quantum-Classical Approach for the Computation of Dislocation Properties in Real Materials: Method, Limitations and Applications

Published

October 16, 2008

Author(s)

Francesca Tavazza, Lyle E. Levine, Anne M. Chaka

Abstract

In this work we introduce a hybrid ab initio-classical simulation methodology designed to incorporate the chemistry into the description of phenomena that, intrinsically, require very large systems to be properly described. This hybrid approach allows us to conduct large-scale atomistic simulations with a simple classical potential (embedded atom method (EAM), for instance) while simultaneously using a more accurate \it ab initio} approach for critical embedded regions. The coupling is made through shared atomic shells where the two atomistic modeling approaches are relaxed in an iterative, self-consistent manner. The magnitude of the incompatibility forces arising in the shared shell is analyzed, and ways to reduce them are discussed. As a test case, the formation energy of a single vacancy in aluminum at different distances from an edge dislocation is studied. Results obtained using the hybrid approach are compared to those obtained using classical methods alone, and the range of validity for the classical approach is evaluated.

Citation

International Journal of Modern Physics C

Pub Type

Journals

Keywords

AI, DFT, dislocation, EAM, hybrid methods, vacancy

Citation

Tavazza, F. , Levine, L. and Chaka, A. (2008), A Hybrid, Quantum-Classical Approach for the Computation of Dislocation Properties in Real Materials: Method, Limitations and Applications, International Journal of Modern Physics C (Accessed April 26, 2024)