Regensburg 2019 – wissenschaftliches Programm

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MM: Fachverband Metall- und Materialphysik

MM 10: Methods in Computational Materials Modelling (methodological aspects, numerics)

MM 10.2: Vortrag

Montag, 1. April 2019, 16:00–16:15, H45

Validation and transferablity of interatomic potentials — •Yury Lysogorskiy, Thomas Hammerschmidt, and Ralf Drautz — ICAMS, Ruhr University Bochum, Germany

Interatomic potentials (IP) are widely used in computational materials science, in particular for simulations that are too computationally expensive for density functional theory (DFT). A large number of IPs is available for a wide range of chemical elements and their mixtures. Most IPs have a limited application range and often there is little information available regarding their performance for specific simulations.

We performed extensive tests for the majority of the potentials for unaries that are available from the OpenKIM and NIST repositories as well as from other sources. The following properties were considered: energy-volume curves, equilibrium bulk modulus, elastic constants, phonon spectrum and density of states, vacancy formation energies, transformation paths, surface energies, thermodynamic properties in the quasiharmonic approximation and thermal expansion. For accessing the transferability of IPs we cover a wide range of atomic environments by considering special random structures with one and two atoms in the unit cell and evaluated their energetic, geometrical and elastic properties. Two typical cases of IP behavior - high accuracy at the expense of low transferability versus low accuracy but higher transferability were identified. The results of our calculations are collected in a specially designed database for further analysis.