About this Abstract |
Meeting |
2023 TMS Annual Meeting & Exhibition
|
Symposium
|
Computational Thermodynamics and Kinetics
|
Presentation Title |
Handling Conditional Convergence in Point Defect Calculations |
Author(s) |
Celine Varvenne, Emmanuel Clouet, Thomas Jourdan |
On-Site Speaker (Planned) |
Celine Varvenne |
Abstract Scope |
Periodic Boundary Conditions are very popular for numerical simulations, but induce artifacts when computing properties of point defects, small clusters or dislocation loops. Their long range elastic fields quantitatively impact the convergence rate and the accuracy of both ab initio calculations of isolated point defect energetics and mesoscopic simulations of ensembles of point defects. Getting rid of these artifacts requires the computation of infinite conditionally convergent sums. Here, we first show the formal equivalence between various numerical regularization techniques of the literature that are based on summations in real space. We then discuss the direct construction of physically-acceptable solutions for the elastic fields in reciprocal space. Accuracy and numerical efficiency of all schemes are compared on metals and defects having various crystalline structures / point symmetries: several SIAs configurations in hcp Zr, and carbon solute in fcc Ni. We finally discuss cases of constant stress/constant strain calculations and linear defects. |
Proceedings Inclusion? |
Planned: |
Keywords |
Computational Materials Science & Engineering, Nuclear Materials, Other |