Ab initio -based modeling of plasticity and related phenomena

Ab initio modeling of plasticity has been a long-standing challenge. Because of the intrinsically large-scale nature of phenomena such as plasticity and fracture, such calculations are typically done with force fields that are simplistic approximations of complex interatomic interactions and cannot provide insight into electronic structure-mediated mechanisms, which is required especially in the presence of chemical changes, for example in embrittlement. Ab initio-based modeling is desired for better descriptive and predictive power, to benchmark force fields at the scale of the phenomena, and to gain mechanistic understanding necessary for rational rather than ad hoc material design. We overview the status and perspectives of ab initio-based modeling of plasticity-related phenomena. We first consider small-scale modeling with DFT (density functional theory) that is often used to infer plastic properties, before focusing on direct larger-scale ab initio-based modeling of such phenomena with methods including density functional tight binding, orbital-free (OF) DFT, and DFT/OF-DFT coupled with molecular mechanics (QM/MM) or quasicontinuum approaches that are able to treat billions of atoms. We highlight elements of insight gained in respective works which were only possible at the electronic structure level. We conclude that with the ongoing progress in large-scale electronic structure methods—both those that already have been used for simulations of plasticity and those that still have not but carry promise in this domain—direct ab initio level modeling of plasticity and related phenomena will become more important in the near future, increasing the impact of atomistic modeling on materials science.