Dresden 2011 – scientific programme
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MM: Fachverband Metall- und Materialphysik
MM 28: Topical Session Electron Theory III
MM 28.1: Talk
Wednesday, March 16, 2011, 15:45–16:00, IFW A
Parameterization of bond-order potentials from first principles — Martin Reese1,2, •Matous Mrovec2,1, Christian Elsässer2,1, Alexander Urban3, and Bernd Meyer3 — 1IZBS, Karlsruhe Institut of Technology, Karlsruhe, Germany — 2Fraunhofer IWM, Freiburg, Germany — 3ICMM and CCC, University of Erlangen-Nürnberg, Erlangen, Germany
Bond-order potentials (BOPs) provide a real-space semi-empirical description of interactions between atoms based on the chemically intuitive tight-binding approximation for the electronic structure. The BOP approach offers two key advantages that are crucial for a successful modeling of extended crystal defects in covalent materials and transition metals. First, due to its quantum mechanical character it conveys a physically sound description of chemical bonding rather than ad hoc functional forms, which are common to classical empirical interatomic potentials. Second, its real space parameterization and computationally linear scaling enables to carry out computer simulations of large and complex systems, which are usually inaccessible to rigorous first-principles density-functional-theory (DFT) methods. We will present a recently developed atomic-orbital-projection approach that enables to construct BOPs for transition metals and their compounds in a rigorous manner from DFT results via tight-binding models. The success of these BOPs will be demonstrated on studies of extended defects, in particular lattice dislocations and grain boundaries.