Dimer Reference Embedded Atom Method (DR-EAM) and Its Application to Vacancy Formation Energy of FCC Metals
Yingchen Yin, Kunio Takahashi, Xiaoying Yuan, Tadao Onzawa
Embedded atom method (EAM) has been successfully applied to investigate surface properties and simulate diffusion phenomena, which do a great help to study micro-joining process. However, because its theory and parameterization are based on bulk system it fails in solving some problems of non-bulk system. In order to increase the applicability of EAM to non-bulk system, a new scheme of EAM, DR-EAM is proposed. In this scheme, the dimer structure is selected as a common reference structure and the parameters are derived from dimer and some bulk properties. In this work, the DR-EAM parameters of 7 kinds of FCC metals are renewed by revising the modeling system and including some experimental data of dimer. The features of their energy-distance curves are discussed and it shows the need of including angular dependency of electronic density. The vacancy formation energies, which play an important role in the diffusion process, are calculated and compared with experimental data.