Dresden 2017 – wissenschaftliches Programm
MM 65.1: Vortrag
Donnerstag, 23. März 2017, 15:45–16:00, BAR 205
Validation and uncertainty assessment of bond-order potentials for transition metals — •Matous Mrovec, Thomas Hammerschmidt, and Ralf Drautz — ICAMS, Ruhr-Univerität Bochum
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 particular focus is given to crystal defects which are often used to validate the accuracy and reliability of interatomic potentials for transition metals.