Berlin 2008 – wissenschaftliches Programm

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SYMS: Symposium Modern developments in multiphysics materials simulations

SYMS 1: Modern developments in multiphysics materials simulations I

SYMS 1.1: Hauptvortrag

Donnerstag, 28. Februar 2008, 14:00–14:30, A 151

Valence-dependent analytic bond-order potentials for metals and semiconductors — •D.G. Pettifor, R. Drautz, and T. Hammerschmidt — Department of Materials, University of Oxford, Oxford, United Kingdom

Valence-dependent analytic bond-order potentials (BOPs) for transition metals and semiconductors are derived by systematically coarse graining from the electronic to atomistic modelling hierarchies. First, the density functional theory (DFT) electronic structure and binding energy is simplified by introducing the tight-binding (TB) bond model whose parameters are determined directly from the DFT results. Second, this TB electronic structure is coarse grained through atom-centred moments and bond-centred interference paths, thereby predicting the analytic form of the interatomic BOP for both close-packed transition metals [1] and open-packed semiconductors [2]. The resultant BOPs are valence-dependent and provide the first interatomic potentials that predict the observed structural changes across the d-valent transition metals series and the sp-valent elements. Current development of these potentials for simulating transition metal alloys and the growth of semiconductor films is discussed.

[1] R. Drautz and D.G. Pettifor, Phys. Rev. B 74 (2006) 174117.

[2] R. Drautz, X.W. Zhou, D.A. Murdick, B. Gillespie, H.N.G. Wadley and D.G. Pettifor, Prog. Mater. Sci. 52 (2007) 196.