Embedded-atom model

The chemical potentials have been evaluated numerically by Hagen using embedded atom models for the defect energies [10]. An important finding was that good quantitative... 

Haftel Ml, Rosen M. 2001. Surface embedded atom model of the electrolyte-metal interface. Phys Rev B 64 195405. 

Figure 15 Melting temperature and latent heat for sodium clusters of different sizes. Open and closed symbols mark results for the singly charged and the neutral clusters, respectively, and the squares and the circles represent results from calculations using the tight-binding and the embedded-atom model, respectively. Finally, experimental results are shown with the triangles. Reproduced with permission of American Institute of Physics from 52...

Foiles, S.M. Chapter 3, Calculation of the surface segregation of alloys using the embedded atom model. In Surface Segregation Phenomena (ed. Dowben, P.A. and Miller, A.). Boca Raton, FL CRC Press, 1990, pp. 79-105. 

Structure and Composition of Au3Pd(110) Determined by LEED and a Monte Carlo-Embedded Atom Model Calculation (Sim.)... 

Fig. 20. Schematic missing row model of a fee (110) surface (1x2 reconstruction). The structural parameters are, for example, evaluated for Au3Pd(110) using LEED and a combined Monte Carlo and embedded atom model calculation (Table II) [39]. Reprinted with permission from J. Kuntze et al., Phys. Rev. B60,9010 (1999), 1999, The American Physical Society.

Chapter 11 deals with the tight-binding and the embedded-atom models of solid state. The method of the local combination of atomic orbitals is described. We present examples of the technique application. Description of atom systems in the embedded-atom method, embedding functions and applications are considered. In conclusion the reader will find the review of interatomic pair potentials. 

Where is the force acting on the i-th atom or particle at time t and is obtained as the negative gradient of the interaction potential U, m. is the atomic mass and the atomic position. The interaction potentials together with their parameters, describe how the particles in a system interact with each other (so-called force field). Force field may be obtained by quantum method (e g., Ab initio), empirical method (e g., Lennard-Jones, Mores, and Bom-Mayer) or quantum-empirical method (e.g., embedded atom model, glue model, bond order potential). 

The embedded-atom model was developed by Daw and Baskes [20] and was originally intended to describe metallic systems. In general, the potential takes the... 

More recently, a particularly interesting new formulation of the embedded-atom model, called the force-matching method has been published by Ercolessi and Adams [21]. In this work, no prior assumptions were made on the actual functional forms in Eqs. 4.34 and 4.35. All functions were described by splines, and the splines were fitted such that the difference between the forces predicted by the... 

Although the embedded atom model proved to be a good potential for metallic systems, it fails to describe covalent materials, such as semiconductors. The reason for this is that the electron density in Eq. 4.35 is assumed to be isotropic, which is a good approximation in close packed systems, like fee crystals, but in the case of covalent bonds, the electron density is higher along the bonds. In order to correct this, an angle-dependent density term was introduced by Baskes [22] for silicon... 

Taylor showed an elegant generalisation of the modified embedded atom model in [24]. In this work, he formulated a Taylor-expansion of the total energy functional around the ground-state density of atoms in terms of density variations, which led to a general expression for the total energy of the system as a function of the atomic coordinates. The energy of an atomic system is determined as a functional of the atomic density as... 

This expression has the same form as the modified embedded atom model. Taylor represented the local atomic density by bond-order parameters and different radial functions as discussed in Sect. 2.3.1 in Chap. 2. By choosing appropriate radial functions, he obtained the original modified embedded-atom formula, but systematic improvement of the formula is also possible in his framework. 

Two-body potentials are typically a good approximation of neutral atoms such as noble gases, which are dominated by attractive van der Waals forces at separations and with strong repulsion at close distances due to Pauli s exclusion principle. The electronic distributions of other systems, such as covalently bonded materials, are modeled more accurately by more complicated environmentally dependent semiempirical potentials. These include bond-order potentials like Tersoff [11], Brenner [12], and ReaxFF [13] and embedded atom model (EAM) [14] potentials, which are particularly applicable to metallic systems. 

Garcia-Rodeja, J., Rey> C.> Gallego, L. J.> Alonso, J. A. (1994). Molecular-dynamics study of the structures, binding energies, and melting of clusters of fee transition and noble metals using the voter and chen version of the embedded-atom model. Physical Review B, 49, 8495. 

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