Embedded-atom-method interatomic potentials from lattice inversion

Abstract

The present work develops a physically reliable procedure for building theembedded-atom-method (EAM) interatomic potentials for the metals with fcc, bcc andhcp structures. This is mainly based on Chen–Möbius lattice inversion (Chen et al 1997 Phys. Rev. E 55 R5) and first-principles calculations. Following Baskes (Baskes et al 2007 Phys. Rev. B 75 094113), this new version of the EAM eliminates all of theprior arbitrary choices in the determination of the atomic electron density andpair potential functions. Parameterizing the universal form deduced from thecalculations within the density-functional scheme for homogeneous electron gas as theembedding function, the new-type EAM potentials for Cu, Fe and Ti metals havesuccessfully been constructed by considering interatomic interactions up to the fifthneighbor, the third neighbor and the seventh neighbor, respectively. The predictionsof elastic constants, structural energy difference, vacancy formation energy andmigration energy, activation energy of vacancy diffusion, latent heat of melting andrelative volume change on melting all satisfactorily agree with the experimentalresults available or first-principles calculations. The predicted surface energies forlow-index crystal faces and the melting point are in agreement with the experimentaldata to the same extent as those calculated by other EAM-type potentials suchas the FBD-EAM, 2NN MEAM and MS-EAM. In addition, the order amongthe predicted low-index surface energies is also consistent with the experimentalinformation.