Effective potentials for quasicrystals fromab-initiodata

Abstract\n Classical effective potentials are indispensable for any large-scale \natomistic simulations, and the relevance of simulation results \ncrucially depends on the quality of the potentials used. For complex \nalloys like quasicrystals, however, realistic effective potentials are \npractically inexistent. We report here on our efforts to develop \neffective potentials especially for quasicrystalline alloy systems. \nWe use the so-called force matching method, in which the potential \nparameters are adapted so as to optimally reproduce the forces \nand energies in a set of suitably chosen reference configurations. \nThese reference data are calculated with ab-initio methods. \nAs a first application, EAM potentials for decagonal Al-Ni-Co, \nicosahedral Ca-Cd, and both icosahedral and decagonal Mg-Zn \nquasicrystals have been constructed. The influence of the potential \nrange and degree of specialisation on the accuracy and other properties \nis discussed and compared.