ICAMS / Interdisciplinary Centre for Advanced Materials Simulation

Research Highlights

BOPcat software package for the construction and testing of tight-binding models and bond-order potentials

A. N. C. Ladines, T. Hammerschmidt, R. Drautz.

Atomistic models like tight-binding (TB), bond-order potentials (BOP) and classical potentials describe the interatomic interaction in terms of mathematical functions with parameters that need to be adjusted for a particular material. The procedures for constructing TB/BOP models differ from the ones for classical potentials. We developed the BOPcat software package as a modular python code for the construction and testing of TB/BOP parameterizations. It makes use of atomic energies, forces and stresses obtained by TB/BOP calculations with the BOPfox software package. It provides a graphical user interface and flexible control of raw reference data, of derived reference data like defect energies, of automated construction and testing protocols, and of parallel execution in queuing systems. We demonstrate the concepts and usage of the BOPcat software and illustrate its key capabilities by exemplary constructing and testing a parameterization of a magnetic BOP for Fe. We provide a parameterization protocol with a successively increasing set of reference data that leads to good transferability to a variety of properties of the ferromagnetic bcc groundstate and to crystal structures which were not part of the training set.

Workflow of constructing and testing of tight-binding models and analytic bond-order potentials with the BOPcat software package.