In computational chemistry and computational physics, the embedded atom model, embedded-atom method or EAM, is an approximation describing the energy between atomsand is a type of interatomic potential. The energy is a function of a sum of functions of the separation between an atom and its neighbors. In the original model, by Murray Daw and Mike Baskes,[1] the latter functions represent the electron density. The EAM is related to the second moment approximation to tight binding theory, also known as the Finnis-Sinclair model. These models are particularly appropriate for metallic systems.[2] Embedded-atom methods are widely used in molecular dynamics simulations.
In a simulation, the potential energy of an atom,
i
Ei=F\alpha\left(\sumj ≠ \rho\beta(rij)\right)+
| 1 | |
| 2 |
\sumj ≠ \phi\alpha\beta(rij)
rij
i
j
\phi\alpha\beta
\rho\beta
j
\beta
i
F
i
\alpha
Since the electron cloud density is a summation over many atoms, usually limited by a cutoff radius, the EAM potential is a multibody potential. For a single element system of atoms, three scalar functions must be specified: the embedding function, a pair-wise interaction, and an electron cloud contribution function. For a binary alloy, the EAM potential requires seven functions: three pair-wise interactions (A-A, A-B, B-B), two embedding functions, and two electron cloud contribution functions. Generally these functions are provided in a tabularized format and interpolated by cubic splines.