|About this Abstract
||2017 TMS Annual Meeting & Exhibition
||Computational Methods and Experimental Approaches for Uncertainty Quantification and Propagation, Model Validation, and Stochastic Predictions
||Validation and Uncertainty Assessment of Bond-order Potentials for Transition Metals
||Matous Mrovec, Thomas Hammerschmidt, Yi-Shen Lin, Vaclav Vitek, Ralf Drautz
|On-Site Speaker (Planned)
Bond-order potentials (BOPs) present a bridge between electronic and atomistic modeling. They are based on the tight-binding (TB) approximation, but the exact diagonalization of the Hamiltonian is replaced by an approximate evaluation of the local densities of states, which leads to a real-space formalism and linear-scaling computation of the energy and forces for a system of interacting atoms. The BOP formalism can be carried out using either a numerical integration or an analytical expansion of the response functions. In this work we present a detailed comparison of the k-space TB with the numerical and analytic BOPs for several transition metals, and assess the differences of the three approaches. The tests are carried out not only for properties of bulk phases but also crystal defects. Particular focus is given to dislocation behavior, which is often used to validate the accuracy and reliability of interatmoic potentials for transition metals.